mirror of https://github.com/stella-emu/stella.git
Tweaked ContextMenu so that an item is selected/committed only when the
left mouse button is pressed and released on the item (should fix problems with accidentally selecting an item). Also added 'Escape' key to mean "cancel/remove context menu". Updated '-help' commandline argument to recent additions. Huge amount of work on the documentation. It's probably not complete, but it's turning into a project in itself. git-svn-id: svn://svn.code.sf.net/p/stella/code/trunk@776 8b62c5a3-ac7e-4cc8-8f21-d9a121418aba
This commit is contained in:
stephena
parent
09a8f8f10d
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8aed4f81a9
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@ -1,753 +0,0 @@
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20050717 bkw
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This alpha build of Stella contains an incomplete version of the debugger.
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What the debugger can do:
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- Display registers and memory
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- Dump state of TIA and RIOT, with things like joystick directions and
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NUSIZx decoded into English (more-or-less).
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- Change registers/memory, including toggles for flags in P register
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- Single step/trace
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- Breakpoints - break running program and enter debugger when the
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Program Counter hits a predefined address. You can set as many
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breakpoints as you want.
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- Conditional breakpoints - Break running program when some arbitrary
|
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condition is true (e.g. "breakif {a == $7f && c}" will break when the
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Accumulator value is $7f and the Carry flag is true, no matter where
|
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in the program this happens). Unlike the cond breaks in PCAE, Stella's
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are *fast*: the emulation will run at full speed unless you use lots
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of breakif's at the same time, or have a slow CPU
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- Watches - View contents of a location/register before every
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debugger prompt.
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- Traps - Like breakpoints, but break on read/write/any access to
|
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*any* memory location.
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- Frame advance (automatic breakpoint at beginning of next frame)
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You can advance multiple frames with one command.
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- Disassembly
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- Support for DASM symbol files (created with DASM's -s option),
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including automatically loading symbol files if they're named
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romname.sym
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- Built-in VCS.H symbols, if no symbol file is loaded
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- Symbolic names in disassembly
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- Symbolic names accepted as input
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- Tab completion for commands and symbol names
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- Graphical editor for RIOT RAM. Acts a lot like a spreadsheet.
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Input in hex, with displays for label/decimal/binary for
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currently-selected location.
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- GUI CPU state window
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- Cheat system (similar to MAME) (still needs a way to save/load cheats)
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- Reset the 6502
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- Input and output in hex, decimal, or binary
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- Start emulator in debugger (via command-line option "-debug")
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- Save CLI session to a text file.
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- Supports hex, decimal, and binary input and output almost everywhere.
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(disassembly is still hex)
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- Support for bank switching. You can see how many banks a cart has,
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and switch banks. There's still more to be done here though.
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- Patching ROM in-place. Currently there's no way to save the patched
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ROM though.
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- Registers/memory that get changed by the CPU during debugging are
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highlighted when they're displayed
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- Scanline advance (like frame advance, break at beginning
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of next scanline).
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- TIA display is updated during step/trace, so we can see our
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scanlines being drawn as it happens. This isn't 100% perfect: unlike
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a real TIA, the one in Stella only updates when it's written to.
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- Script (batch) file support, including auto-running a script file
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named after the ROM image.
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- Saving the current debugger state to a script file (including
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breakpoints, traps, etc).
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- Built-in functions for use with "breakif", to support common conditions
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(such as breaking when the user presses Game Select...)
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- Save patched ROM ("saverom filename.bin").
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Planned features for Stella 2.0 release:
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- Graphical TIA tab, with register names and GUI buttons for
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various bits (e.g. click ENAM0 to turn it on). This has been started
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on already.
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- GUI Disassembly window, scrollable, with checkboxes for breakpoints
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(also perhaps 2 panes in this window so you can see 2 parts of the
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code at once)
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- Bankswitch support in the debugger for the few remaining cart types
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that aren't supported.
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- Patch ROM support for a few cart types doesn't work. Must fix.
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- Some way to control joystick/etc. input from within the debugger.
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- Source-level debugging: if a DASM .lst file is available, we'll show
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the listing in the ROM tab instead of a disassembly. This is already
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availabe in a very crude form ("loadlist" and "list" commands).
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- More "special variables" for the expression parser. Currently, you can
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use all the CPU registers and flags in expressions (e.g. "print a+1" does
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what you expect), and the pseudo-variables "_scan" and "_bank" (which
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evaluate the the current scanline and bank number). Need to add more TIA,
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RIOT registers too. Also, more functions for the builtin function lib.
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Future plans (post 2.0):
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- Possibly a mini-assembler
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- Support for extra RAM in Supercharger and other cart types.
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- Possibly support for recording and playing back input files, like
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MAME. This isn't a debugger feature per se, but it'll make it easier
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to reliably trigger a bug so you can debug it
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- Graphics ROM view, so you can see your sprite data (it might still
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be upside-down though :)
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- Various new GUI enhancements
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How to use the debugger
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-----------------------
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Pressing ` (aka backtick, backquote, grave accent) toggles the debugger on
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& off. When you exit the debugger, the emulation resumes at the current
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program counter, and continues until either a breakpoint/trap is hit,
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or the ` key is pressed again. Pressing Ctrl-Tab cycles between tabs
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from left to right, and Shift-Ctrl-Tab cycles from right to left.
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Pressing Tab cycles between widgets in the current tab.
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|
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You can also enter the debugger by giving a breakpoint on the command line:
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; will enter the debugger the first time the instruction at "kernel" runs
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stella -break kernel mygame.bin
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; $fffc is the 6502/6507 init vector. This command will break and enter the
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; debugger before the first 6507 instruction runs, so you can debug the
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; startup code:
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stella -break "*($fffc)" mygame.bin
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Tabs:
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|
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The top-level user interface uses tabs to select the current debugger
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mode. Not all the tabs are implemented yet: those that aren't will just
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show up as a blank tab.
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The tabs that are implemented so far:
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- Prompt tab
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This is a command-line interface, similar to the DOS DEBUG command
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or Supermon for the C=64. It shows you the current CPU state, including
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the disassembly of the instruction pointed to by the Program Counter.
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This instruction is the NEXT one that will execute, NOT the one that
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just executed!
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Editing keys work about like you'd expect them to: Home, End, Delete,
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arrows, etc. To scroll with the keyboard, use Shift-PageUp and
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Shift-PageDown or Shift-Up and Shift-Down arrow keys. You can also
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scroll with the mouse. Copy and paste is not (yet?) supported.
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To see the available commands, enter "help" or "?". Most commands can
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be abbreviated: instead of "clearbreaks", you can type "clear" or
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even just "cl". However, "c" by itself is the Toggle Carry command.
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|
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Bash-style tab completion is supported for commands and labels (see below)
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For now, there are some functions that only exist in the prompt. We
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intend to add GUI equivalents for all (or almost all?) of the prompt
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commands by the time we release Stella 2.0. People who like command
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||||
prompts will be able to use the prompt, but people who hate them will
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have a fully functional debugger without typing (or without typing
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much, anyway).
|
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|
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- Status
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|
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Before each prompt, you'll see a dump of the current processor
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status, plus any watches you've set (see section on watches
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below), plus a disassembly of the instruction at the current
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Program Counter. This is the next instruction that will execute;
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it hasn't been executed yet.
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PC=f000 A=01 X=02 Y=03 S=ff P=21/nv-bdizC Cycle 12345
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$f000 a2 ff LDX #ff ; 2
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>
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This is telling us a lot of information:
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- PC=f000 A=01 X=02 Y=03 S=ff
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The Program Counter, Accumulator, X, Y, and Stack Pointer registers.
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|
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- P=21/nv-bdizC
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The Processor Status register. The "21" is the hex value of the
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register, and the "nv-bdizC" shows us the individual flags. Flags
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with capital letters are set, and lowercase means clear. In this
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example, only the Carry bit is set.
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|
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- Cycle 12345
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This counter gets reset at the beginning of each frame, when
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VSYNC is strobed. In this example, we're 12345 (decimal) cycles
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past the beginning of the frame.
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||||
|
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- $f000 a2 ff LDX #ff ; 2
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Disassembly of the instruction the PC points to. This is the next
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instruction that will execute (when we exit the debugger, or via the
|
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"step" or "trace" commands). The "a2 ff" is the raw machine code
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for this instruction. The "; 2" is a cycle count: this instruction
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will take 2 cycles to execute.
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|
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WARNING: the cycle count in the disassembly does NOT include extra
|
||||
cycles caused by crossing page boundaries. Also, Branch instructions
|
||||
are shown as 2 cycles, as though they're not going to be taken. A
|
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branch that's taken adds a cycle, of course.
|
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|
||||
The ">" is where your commands will appear as you type them.
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|
||||
|
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- Tab completion
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|
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While entering a command or label, you can type a partial name and
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||||
press the Tab key to attempt to auto-complete it. If you've ever used
|
||||
"bash", this will be immediately familiar. If not, try it: load up
|
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a ROM, go to the debugger, type "print w" (but don't press Enter),
|
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then hit Tab. The "w" will change to "WSYNC" (since this is the only
|
||||
built-in label starting with a "w"). If there are multiple possible
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completions (try with "v" instead of "w"), you'll see a list of them,
|
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and your partial name will be completed as far as possible.
|
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|
||||
Tab completion works on all labels: built-in, loaded from a symbol file,
|
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or set during debugging with the "define" command. However, it does not
|
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yet work on functions defined with the "function" command, nor does it
|
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work on filenames.
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|
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- Expressions
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Almost every command takes a value: the "a" command takes a
|
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byte to stuff into the accumulator, the "break" command
|
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takes an address to set/clear a breakpoint at. These values
|
||||
can be as a hex constant ($ff, $1234), or as complex as
|
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"the low byte of the 16-bit value located at the address
|
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pointed to by the binary number 1010010110100101" (which
|
||||
would be "@<\1010010110100101"). You can also use registers
|
||||
and labels in expressions.
|
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|
||||
You can use arithmetic and boolean operators in expressions. The
|
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syntax is very C-like. The operators supported are:
|
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|
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+ - * / (add, subtract, multiply, divide: 2+2 is 4)
|
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% (modulus/remainder: 3%2 is 1)
|
||||
& | ^ ~ (bitwise AND, OR, XOR, NOT: 2&3 is 2)
|
||||
&& || ! (logical AND, OR, NOT: 2&&3 is 1, 2||0 is 0)
|
||||
( ) (parentheses for grouping: (2+2)*3 is 12)
|
||||
* @ (byte and word pointer dereference: *$80 is the byte stored
|
||||
at location $80)
|
||||
[ ] (array-style byte pointer dereference: $80[1] is the byte
|
||||
stored at location ($80+1) or $81)
|
||||
< > (prefix versions: low and high byte. <$abcd is $cd)
|
||||
== < > <= >= !=
|
||||
(comparison: equality, less-than, greater-than, less-or-equals,
|
||||
greater-or-equals, not-equals)
|
||||
<< >> (bit shifts, left and right: 1<<1 is 2, 2>>1 is 1)
|
||||
|
||||
Division by zero is not an error: it results in zero instead.
|
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|
||||
None of the operators change the values of their operands. There
|
||||
are no variable-assignment or increment/decrement operators. This
|
||||
may change in the future, which is why we used "==" for equality
|
||||
instead of just "=".
|
||||
|
||||
The bitwise and logical boolean operators are different in that the
|
||||
bitwise operators operate on all the bits of the operand (just like
|
||||
AND, ORA, EOR in 6502 asm), while the logical operators treat their
|
||||
operands as 0 for false, non-zero for true, and return either 0 or 1.
|
||||
So $1234&$5678 results in $1230, whereas $1234&&$5678 results in 1.
|
||||
This is just like C or C++...
|
||||
|
||||
Like some programming languages, the debugger uses prefixed characters
|
||||
to change the meaning of an expression. The prefixes are:
|
||||
|
||||
- Dereference prefixes:
|
||||
|
||||
- "*"
|
||||
Dereference a byte pointer. "*a" means "the byte at the address that
|
||||
the A register points to". If A is 255 (hex $ff), the result will be
|
||||
the value currently stored in memory location 255. This operator
|
||||
will be very familiar to you if you're a C or C++ programmer. It's
|
||||
equivalent to the PEEK() function in most 8-bit BASICs. Also, the
|
||||
debugger supports array-like byte dereferences: *address can be
|
||||
written as address[0]. *(address+1) can be written as address[1],
|
||||
etc.
|
||||
|
||||
- "@"
|
||||
Dereference a pointer to a word. This is just like the "*" byte deref,
|
||||
except it refers to a 16-bit value, occupying 2 locations, in
|
||||
low-byte-first format (standard for the 6507).
|
||||
|
||||
The following are equivalent:
|
||||
|
||||
@address
|
||||
*address+$100**(address+1)
|
||||
address[0]+#256*address[1]
|
||||
|
||||
(TODO: add (indirect),y and (indirect,x) syntax)
|
||||
|
||||
- Hi/Lo Byte Prefixes
|
||||
|
||||
- "<"
|
||||
Take the low byte of a 16-bit value. This has no effect on an 8-bit
|
||||
value: "a" is equal to "<a". However, "<$1234" equals "$34".
|
||||
|
||||
- ">"
|
||||
Take the high byte of a 16-bit value. For 8-bit values such as
|
||||
the Accumulator, this will always result in zero. For 16-bit values,
|
||||
"<$1234" = "$12".
|
||||
|
||||
- Number Base Prefixes
|
||||
|
||||
- "#"
|
||||
Treat the input as a decimal number.
|
||||
|
||||
- "$"
|
||||
Treat the input as a hex number.
|
||||
|
||||
- "\"
|
||||
Treat the input as a binary number.
|
||||
|
||||
These only have meaning when they come before a number, not a
|
||||
label or a register. "\1010" means 10 decimal. So do "$0a" and
|
||||
"#10". "a" by itself is always the Accumulator, no matter what
|
||||
the default base is set to.
|
||||
|
||||
If you don't specify any number base prefix, the number is
|
||||
assumed to be in the default base. When you first start Stella,
|
||||
the default base is 16 (hexadecimal). You can change it with the
|
||||
"base" command.
|
||||
|
||||
Remember, you can use arbitrarily complex expressions with any
|
||||
command that takes arguments (except the ones that take filenames,
|
||||
like "loadsym").
|
||||
|
||||
|
||||
- Breakpoints, watches and traps, oh my!
|
||||
|
||||
- Breakpoints
|
||||
|
||||
A breakpoint is a "hotspot" in your program that causes the emulator
|
||||
to stop emulating and jump into the debugger. You can set as many
|
||||
breakpoints as you like. The command is "break xx" where xx is any
|
||||
expression. If you've created a symbol file, you can use labels.
|
||||
|
||||
Example: you've got a label called "kernel". To break there,
|
||||
the command is "break kernel". After you've set the breakpoint,
|
||||
exit the debugger ("quit" or click the Exit button). The emulator
|
||||
will run until it gets to the breakpoint, then it will enter the
|
||||
debugger with the Program Counter pointing to the instruction
|
||||
at the breakpoint.
|
||||
|
||||
Breakpoints happen *before* an instruction is executed: the
|
||||
instruction at the breakpoint location will be the "next"
|
||||
instruction.
|
||||
|
||||
To remove a breakpoint, you just run the same command you used to
|
||||
set it. In the example, "break kernel" will remove the breakpoint.
|
||||
The "break" command can be thought of as a *toggle*: it turns the
|
||||
breakpoint on & off, like a light switch.
|
||||
|
||||
You could also use "clearbreaks" to remove all the breakpoints. Also,
|
||||
there is a "listbreaks" command that will list them all.
|
||||
|
||||
- Conditional Breaks
|
||||
|
||||
A conditional breakpoint causes the emulator to enter the debugger when
|
||||
some arbitrary condition becomes true. "True" means "not zero" here:
|
||||
"2+2" is considered true because it's not zero. "2-2" is false, because
|
||||
it evaluates to zero. This is exactly how things work in C and lots
|
||||
of other languages, but it might take some getting used to if you've
|
||||
never used such a language.
|
||||
|
||||
Suppose you want to enter the debugger when the Game Reset switch is
|
||||
pressed. Looking at the Stella Programmers' Guide, we see that this
|
||||
switch is read at bit 0 of SWCHB. This bit will be 0 if the switch is
|
||||
pressed, or 1 otherwise.
|
||||
|
||||
To have an expression read the contents of an address, we use the
|
||||
dereference operator "*". Since we're looking at SWCHB, we need
|
||||
"*SWCHB".
|
||||
|
||||
We're only wanting to look at bit 0, so let's mask off all the other
|
||||
bits: "*SWCHB&1". The expression now evaluates to bit 0 of SWCHB. We're
|
||||
almost there: this will be 1 (true) if the switch is NOT pressed. We
|
||||
want to break if it IS pressed...
|
||||
|
||||
So we invert the sense of the test with a logical NOT operator (which
|
||||
is the "!" operator): !(*SWCHB&1). The parentheses are necessary as
|
||||
we want to apply the ! to the result of the &, not just the first term
|
||||
(the "*SWCHB").
|
||||
|
||||
"breakif !(*SWCHB&1)" will do the job for us. However, it's an ugly mess
|
||||
of letters, numbers, and punctuation. We can do a little better:
|
||||
|
||||
"breakif { !(*SWCHB & 1 ) }" is a lot more readable, isn't it? If
|
||||
you're going to use readable expressions with spaces in them,
|
||||
enclose the entire expression in curly braces {}.
|
||||
|
||||
There is one annoyance about this complex expression: once we
|
||||
remove the conditional break with "delbreakif" or "clearbreaks",
|
||||
we'd have to retype it (or search backwards with the up-arrow key)
|
||||
if we wanted to use it again.
|
||||
|
||||
We can avoid this by defining the expression as a function, then using
|
||||
"breakif function_name":
|
||||
|
||||
function gameReset { !(*SWCHB & 1 ) }
|
||||
breakif gameReset
|
||||
|
||||
Now we have a meaningful name for the condition, so we can use it again.
|
||||
Not only that: we can use the function as part of a bigger expression.
|
||||
Suppose we've also defined a gameSelect function that evaluates to true
|
||||
if the Game Select switch is pressed. We want to break when the user
|
||||
presses both Select and Reset:
|
||||
|
||||
breakif { gameReset && gameSelect }
|
||||
|
||||
If you've defined a lot of complex functions, you probably will
|
||||
want to re-use them in future runs of the debugger. You can save
|
||||
all your functions, breakpoints, conditional breaks, and watches
|
||||
with the "save" command. If you name your saved file the same
|
||||
as the ROM filename, it'll be auto-loaded next time you load the
|
||||
same ROM in Stella. The save file is just a plain text file called
|
||||
"filename.stella", so you can edit it and add new functions, etc.
|
||||
|
||||
Conditional breaks appear in "listbreaks", numbered starting from
|
||||
zero. You can remove a cond. break with "delbreakif number", where
|
||||
the number comes from "listbreaks".
|
||||
|
||||
- Watches
|
||||
|
||||
A watch is an expression that gets evaluated and printed before
|
||||
every prompt. This is useful for e.g. tracking the contents of a
|
||||
memory location while stepping through code that modifies it.
|
||||
|
||||
You can set up to 10 watches (in future the number will be unlimited).
|
||||
Since the expression isn't evaluated until it's used, you can include
|
||||
registers: "watch *y" will show you the contents of the location
|
||||
pointed to by the Y register, even if the Y register changes.
|
||||
|
||||
The watches are numbered. The numbers are printed along with the
|
||||
watches, so you can tell which is which. To delete a watch use the
|
||||
"delwatch" command with the watch number (1 to whatever). You can
|
||||
also delete them all with the "clearwatches" command.
|
||||
|
||||
Note that there's no real point in watching a label or CPU register
|
||||
without dereferencing it: Labels are constants, and CPU registers
|
||||
are already visible in the prompt status.
|
||||
|
||||
- Traps
|
||||
|
||||
A trap is similar to a breakpoint, except that it catches
|
||||
accesses to a memory address, rather than specific location in the
|
||||
program. They're useful for finding code that modifies TIA registers
|
||||
or memory.
|
||||
|
||||
An example: you are debugging a game, and you want to stop the
|
||||
emulation and enter the debugger whenever RESP0 is strobed. You'd use
|
||||
the command "trap RESP0" to set the trap, then exit the debugger. The
|
||||
emulator will run until the next time RESP0 is accessed (either read
|
||||
or write). Once the trap is hit, you can examine the TIA state to
|
||||
see what the actual player 0 position is, in color clocks (or you
|
||||
can in the future when we implement that feature in the TIA dump!)
|
||||
|
||||
Unlike breakpoints, traps stop the emulation *after* the instruction
|
||||
that triggered the trap. The reason for this is simple: until the
|
||||
instruction is executed, the emulator can't know it's going to hit
|
||||
a trap. After the trap is hit, the instruction is done executing,
|
||||
and whatever effects it may have had on e.g. the TIA state have
|
||||
already happened... so we don't have a way to run the emulated CPU
|
||||
in reverse.
|
||||
|
||||
Traps come in two varieties: read access traps and write access traps.
|
||||
It is possible to set both types of trap on the same address (that's
|
||||
what the plain "trap" command does). To set a read or write only trap,
|
||||
use "trapread" or "trapwrite". To remove a trap, you just attempt
|
||||
to set it again: the commands actually toggle the trap on & off. You
|
||||
can also get rid of all traps at once with the "cleartraps" command.
|
||||
|
||||
Use "listtraps" to see all enabled traps.
|
||||
|
||||
- Prompt commands:
|
||||
|
||||
a - Set Accumulator to value xx
|
||||
bank - Show # of banks (with no args), Switch to bank (with
|
||||
1 arg)
|
||||
base - Set default base (hex, dec, or bin)
|
||||
break - Set/clear breakpoint at address (default=pc)
|
||||
c - Carry Flag: set (to 0 or 1), or toggle (no arg)
|
||||
clearbreaks - Clear all breakpoints
|
||||
cleartraps - Clear all traps
|
||||
clearwatches - Clear all watches
|
||||
colortest - Color Test
|
||||
d - Decimal Flag: set (to 0 or 1), or toggle (no arg)
|
||||
define - Define label
|
||||
delwatch - Delete watch
|
||||
disasm - Disassemble from address (default=pc)
|
||||
dump - Dump 128 bytes of memory at address
|
||||
frame - Advance emulation by xx frames (default=1)
|
||||
help - This cruft
|
||||
listbreaks - List breakpoints
|
||||
listtraps - List traps
|
||||
listwatches - List watches
|
||||
loadstate - Load emulator state (0-9)
|
||||
loadsym - Load symbol file
|
||||
n - Negative Flag: set (to 0 or 1), or toggle (no arg)
|
||||
pc - Set Program Counter to address
|
||||
print - Evaluate and print expression in hex/dec/binary
|
||||
ram - Show RAM contents (no args), or set RAM address xx to
|
||||
value yy
|
||||
reload - Reload ROM and symbol file
|
||||
reset - Reset 6507 to init vector (does not reset TIA, RIOT)
|
||||
riot - Show RIOT timer/input status
|
||||
rom - Change ROM contents
|
||||
run - Exit debugger, return to emulator
|
||||
s - Set Stack Pointer to value xx
|
||||
saveses - Save console session to file
|
||||
savestate - Save emulator state (valid args 0-9)
|
||||
savesym - Save symbols to file
|
||||
step - Single step CPU (optionally, with count)
|
||||
tia - Show TIA state
|
||||
trace - Single step CPU (optionally, with count), subroutines
|
||||
count as one instruction
|
||||
trap - Trap read and write accesses to address
|
||||
trapread - Trap read accesses to address
|
||||
trapwrite - Trap write accesses to address
|
||||
undef - Undefine label (if defined)
|
||||
v - Overflow Flag: set (to 0 or 1), or toggle (no arg)
|
||||
watch - Print contents of address before every prompt
|
||||
x - Set X Register to value xx
|
||||
y - Set Y Register to value xx
|
||||
z - Zero Flag: set (to 0 or 1), or toggle (no arg)
|
||||
|
||||
This list may be outdated: see the output of the "help" command
|
||||
for the current list. Commands marked with a * are unimplemented.
|
||||
Commands marked with a + are partially implemented. Most commands can
|
||||
be abbreviated just by typing a partial command: "st" for "step", or
|
||||
"f" for "frame". Where there are conflicts, generally the shortest
|
||||
name is chosen (so "tra" is "trap", not "trapread").
|
||||
|
||||
|
||||
- CPU tab
|
||||
|
||||
(TODO: document this, when it's close enough to finished)
|
||||
|
||||
|
||||
- RAM tab
|
||||
|
||||
This is a spreadsheet-like GUI for inspecting and changing the contents
|
||||
of the 2600's RAM. All 128 bytes of RAM are visible on the screen at
|
||||
once. You can navigate with either the mouse or the keyboard arrow keys.
|
||||
To change a RAM location, either double-click on it or press Enter while
|
||||
it's highlighted. Enter the new value (hex only for now, sorry), then
|
||||
press Enter to make the change. If you change your mind, press Escape
|
||||
and the original value will be restored.
|
||||
|
||||
On the right there are also some buttons to do various things to the
|
||||
currently-selected memory location. The buttons are:
|
||||
|
||||
0 - Set the current location to zero.
|
||||
Inv - Invert the current location (toggle all its bits).
|
||||
Neg - Negate the current location (twos' complement negative).
|
||||
++ - Increment the current location
|
||||
-- - Decrement the current location
|
||||
<< - Shift the current location left. Any bits shifted off the left
|
||||
are lost (they will NOT end up in the Carry flag).
|
||||
>> - Shift the current location right, like << above.
|
||||
|
||||
- Cheat tab
|
||||
|
||||
This tab lets you search memory for values such as lives or remaining
|
||||
energy, but it's also very useful when debugging to determine which
|
||||
memory location holds which quantity.
|
||||
|
||||
Currently, input must be in decimal format, and search results will be
|
||||
shown in decimal (with hex addresses).
|
||||
|
||||
Enter a byte value into the search editbox (0-255) and click 'Search'.
|
||||
All matching address/value pairs will be shown in the listbox to the
|
||||
right. The values in the listbox may be changed using the normal
|
||||
editing operations, and the RAM will be immediately updated. If
|
||||
'Search' is clicked and the inputbox is empty, all RAM locations
|
||||
are returned.
|
||||
|
||||
The 'Compare' button is used to compare the given value using all
|
||||
addresses in the listbox. This may be an absolute number (such as 2),
|
||||
or a comparitive number (such as -1). Using a '+' or '-' operator
|
||||
means 'search addresses for values that have changed by that amount'.
|
||||
|
||||
The following is an example of inspecting all addresses that have
|
||||
decreased by 1:
|
||||
|
||||
Click 'Search' with an empty inputbox. All 128 address/values are
|
||||
returned
|
||||
|
||||
Exit debugger mode and lose a life, let your energy decrease, or
|
||||
do whatever it is you're trying to debug
|
||||
|
||||
Enter debugger mode again, and enter a '-1' in the inputbox
|
||||
|
||||
Click the 'Compare' button, which compares all addresses in the
|
||||
listbox with RAM, and finds all values that have decreased by 1
|
||||
(as compared to their value in the listbox).
|
||||
|
||||
Repeatedly following these steps may help to narrow number of
|
||||
addresses under consideration, and eventually you'll find the
|
||||
memory address you're looking for
|
||||
|
||||
The 'Restart' button restarts the whole procedure (ie, clear the
|
||||
input and listboxes, and allows another search.
|
||||
|
||||
(TODO: need a way to name and save/load the cheats)
|
||||
|
||||
- TIA tab (TODO)
|
||||
|
||||
- ROM tab (TODO)
|
||||
|
||||
Global Buttons:
|
||||
|
||||
There are also buttons on the right that always show up no matter which
|
||||
tab you're looking at. These are always active. They are: Step, Trace,
|
||||
Frame+1, and Exit.
|
||||
|
||||
When you use these buttons, the prompt doesn't change. This means the
|
||||
status lines with the registers and disassembly will be "stale". You
|
||||
can update them just by pressing Enter in the prompt.
|
||||
|
||||
You can also use the Step, Trace and Frame+1 buttons from anywhere in
|
||||
the GUI via the keyboard, with Alt-S, Alt-T and Alt-F.
|
||||
|
||||
|
||||
Tutorial: How to hack a ROM
|
||||
---------------------------
|
||||
|
||||
Here is a step-by-step guide that shows you how to use the debugger to
|
||||
actually do something useful. No experience with debuggers is necessary,
|
||||
but it helps to know at least a little about 6502 programming.
|
||||
|
||||
Step 1: get the Atari Battlezone ROM image. Make sure you've got the
|
||||
regular NTSC version. Load it up in Stella and press TAB to get to
|
||||
the main menu. From there, click on "Game Information". For "Name", it
|
||||
should say "Battlezone (1983) (Atari) [!]" and for MD5Sum it should say
|
||||
"41f252a66c6301f1e8ab3612c19bc5d4". The rest of this tutorial assumes
|
||||
you're using this version of the ROM; it may or may not work with the
|
||||
PAL version, or with any of the various "hacked" versions floating around
|
||||
on the 'net.
|
||||
|
||||
Step 2: Start the game. You begin the game with 5 lives (count the tank
|
||||
symbols at the bottom of the screen).
|
||||
|
||||
Step 3: Enter the debugger by pressing the ` (backquote) key. Don't get
|
||||
killed before you do this, though. You should still have all 5 lives.
|
||||
|
||||
Step 4: Go to the Cheat tab (click on Cheat). The Cheat tab will allow you
|
||||
to search RAM for values such as the number of remaining lives.
|
||||
|
||||
Step 5: In the Cheat tab, enter "5" in the "Enter a value" box and click
|
||||
on Search. This searches RAM for your value and displays the results in
|
||||
the Address/Value list to the right. You should see two results: "00a5:
|
||||
05" and "00ba: 05". These are the only two addresses that currently have
|
||||
the value 5, so they're the most likely candidates for "number of lives"
|
||||
counter. (However, some games might actually store one less than the real
|
||||
number of lives, or one more, so you might have to experiment a bit.
|
||||
Since this is a "rigged demo", I already know Battlezone stores the
|
||||
actual number of lives. Most games do, actually).
|
||||
|
||||
Step 6: Exit the debugger by pressing ` (backquote) again. The game will
|
||||
pick up where you left off.
|
||||
|
||||
Step 7: Get killed! Ram an enemy tank, or let him shoot you. Wait for
|
||||
the explosion to finish. You will now have 4 lives.
|
||||
|
||||
Step 8: Enter the debugger again. The Cheat tab will still be showing.
|
||||
In the "Enter a value" box, delete the 5 you entered earlier, and replace
|
||||
it with a 4. Click "Compare". Now the Address/Value list should only
|
||||
show one result: "00ba: 04". What we did was search within our previous
|
||||
results (the ones that were 5 before) for the new value 4. Address $00ba
|
||||
used to have the value 5, but now it has 4. This means that Battlezone
|
||||
(almost certainly) stores the current number of lives at address $00ba.
|
||||
|
||||
Step 9: Test your theory. Go to the RAM tab and change address $ba to
|
||||
some high number like $ff (you could use the Prompt instead: enter "ram
|
||||
$ba $ff"). Exit the debugger again. You should now see lots of lives
|
||||
at the bottom of the screen (of course, there isn't room to display $ff
|
||||
(255) of them!)... play the game, get killed a few times, notice that
|
||||
you have lots of lives.
|
||||
|
||||
Step 10: Now it's time to decide what sort of "ROM hack" we want to
|
||||
accomplish. We've found the "lives" counter for the game, so we can
|
||||
either have the game start with lots of lives, or change the game
|
||||
code so we can't get killed (AKA immortality), or change the code
|
||||
so we always have the same number of lives (so we never run out, AKA
|
||||
infinite lives). Let's go for infinite lives: it's a little harder than
|
||||
just starting with lots of lives, but not as difficult as immortality
|
||||
(for that, we have to disable the collision checking code, which means
|
||||
we have to find and understand it first!)
|
||||
|
||||
Step 11: Set a Write Trap on the lives counter address: "trapwrite $ba"
|
||||
in the Prompt. Exit the debugger and play until you get killed. When
|
||||
you die, the trap will cause the emulator to enter the debugger with the
|
||||
Program Counter pointing to the instruction *after* the one that wrote
|
||||
to location $ba.
|
||||
|
||||
Step 12: Once in the debugger, press Enter to refresh your prompt. The PC
|
||||
should be at address $f238, instruction "LDA $e1". You want to disassemble
|
||||
the ROM starting a few addresses before this to find the instruction
|
||||
that actually caused the write trap, so enter the command "disasm pc-5"
|
||||
(you may need to press Shift-PageUp afterwards to see the beginning of
|
||||
the disassembly). Take a look at the first few instructions. Do you see
|
||||
the one that affects the lives counter? That's right, it's the "DEC $ba"
|
||||
at location $f236.
|
||||
|
||||
Step 13: Let's stop the DEC $ba from happening. We can't just delete the
|
||||
instruction (it would mess up the addressing of everything afterwards,
|
||||
if it were even possible), but we can replace it with some other
|
||||
instruction(s).
|
||||
|
||||
Since we just want to get rid of the instruction, we can replace it with
|
||||
NOP (no operation). From looking at the disassembly, you can see that
|
||||
"DEC $ba" is a 2-byte long instruction, so we will need two one-byte
|
||||
NOP instructions to replace it. From reading the prompt help (the "help"
|
||||
command), you can see that the "rom" command is what we use to patch ROM.
|
||||
|
||||
Unfortunately, Stella doesn't contain an assembler, so we can't just
|
||||
type NOP to put a NOP instruction in the code. We'll have to use the
|
||||
hex opcode instead.
|
||||
|
||||
Now crack open your 6502 reference manual and look up the NOP
|
||||
instruction's opcode... OK, OK, I'll just tell you what it is: it's $EA
|
||||
(234 decimal). We need two of them, starting at address $f236, so our
|
||||
prompt command looks like:
|
||||
|
||||
rom $f236 $ea $ea
|
||||
|
||||
The debugger should respond with "changed 02 locations". If you run
|
||||
"disasm pc-5" again, you should see the two NOPs at $f236 and $f237.
|
||||
|
||||
Step 14: Test your patch. First, set location $ba to some number of
|
||||
lives that can be displayed on the screen ("poke $ba 3" will do). Now
|
||||
exit the debugger and play the game. You should see 3 lives on the screen.
|
||||
|
||||
Step 15: The crucial test: get killed again! After the explosion, you
|
||||
will *still* see 3 lives: Success! We've hacked Battlezone to give us
|
||||
infinite lives.
|
||||
|
||||
Step 16: Save your work. In the prompt: "saverom bzhack.bin". You now
|
||||
have your very own infinite-lives version of Battlezone. The file will
|
||||
be saved in the current directory (NOT your ROM directory), so you might
|
||||
want to move it to your ROM directory if it isn't the current directory.
|
||||
|
||||
Step 17: Test the new ROM: exit Stella, and re-run it. Open your ROM
|
||||
(or give its name on the command line) and play the game. You can play
|
||||
forever! It worked.
|
||||
|
||||
Now, try the same techniques on some other ROM image (try Pac-Man). Some
|
||||
games store (lives+1) or (lives-1) instead of the actual number,
|
||||
so try searching for those if you can't seem to make it work. Also,
|
||||
some cartridge types include their own RAM. The debugger doesn't (yet)
|
||||
know how to access on-cartridge RAM, so you'll have to use the "bank" and
|
||||
"ram" commands to manually search the address space for the value you're
|
||||
looking for (future versions of the debugger will be smarter about this).
|
||||
|
||||
If you successfully patch a ROM in the debugger, but the saved version
|
||||
won't work, or looks funny, you might need to add an entry to the
|
||||
stella.pro file, to tell Stella what bankswitch and/or TV type to use.
|
||||
That's outside the scope of this tutorial :)
|
||||
|
||||
Of course, the debugger is useful for a lot more than cheating and
|
||||
hacking ROMs. Remember, with great power comes great responsibility,
|
||||
so you have no excuse to avoid writing that game you've been thinking
|
||||
about for so long now :)
|
||||
|
|
@ -0,0 +1,760 @@
|
|||
<html>
|
||||
<head>
|
||||
<title>Stella Debugger</title>
|
||||
</head>
|
||||
<body>
|
||||
|
||||
<h1>Stella Integrated Debugger (a work in progress)</h1>
|
||||
|
||||
<p>The debugger in Stella may never be complete, as we're constantly
|
||||
adding new features requested by homebrew developers. However, even in its
|
||||
current form it's still quite powerful, and is able to boast at least one
|
||||
feature that no other 2600 debugger has; it's <b>completely</b> cross-platform.</p>
|
||||
|
||||
<h2>Here's a list of what the debugger can do so far:</h2>
|
||||
<ul>
|
||||
<li>Display registers and memory</li>
|
||||
<li>Dump state of TIA and RIOT, with things like joystick directions and
|
||||
NUSIZx decoded into English (more-or-less).</li>
|
||||
<li>Change registers/memory, including toggles for flags in P register</li>
|
||||
<li>Single step/trace</li>
|
||||
<li>Breakpoints - break running program and enter debugger when the
|
||||
Program Counter hits a predefined address. You can set as many
|
||||
breakpoints as you want.</li>
|
||||
<li>Conditional breakpoints - Break running program when some arbitrary
|
||||
condition is true (e.g. "breakif {a == $7f && c}" will break when the
|
||||
Accumulator value is $7f and the Carry flag is true, no matter where
|
||||
in the program this happens). Unlike the cond breaks in PCAE, Stella's
|
||||
are *fast*: the emulation will run at full speed unless you use lots
|
||||
of breakif's at the same time, or have a slow CPU.</li>
|
||||
<li>Watches - View contents of a location/register before every
|
||||
debugger prompt.</li>
|
||||
<li>Traps - Like breakpoints, but break on read/write/any access to
|
||||
*any* memory location.</li>
|
||||
<li>Frame advance (automatic breakpoint at beginning of next frame)
|
||||
You can advance multiple frames with one command.</li>
|
||||
<li>Disassembly</li>
|
||||
<li>Support for DASM symbol files (created with DASM's -s option),
|
||||
including automatically loading symbol files if they're named
|
||||
romname.sym</li>
|
||||
<li>Built-in VCS.H symbols, if no symbol file is loaded</li>
|
||||
<li>Symbolic names in disassembly</li>
|
||||
<li>Symbolic names accepted as input</li>
|
||||
<li>Tab completion for commands and symbol names</li>
|
||||
<li>Graphical editor for RIOT RAM. Acts a lot like a spreadsheet.
|
||||
Input in hex, with displays for label/decimal/binary for
|
||||
currently-selected location.</li>
|
||||
<li>GUI CPU state window</li>
|
||||
<!--Cheat system (similar to MAME) (still needs a way to save/load cheats)-->
|
||||
<li>Reset the 6502</li>
|
||||
<li>Start emulator in debugger (via command-line option "-debug")</li>
|
||||
<li>Save CLI session to a text file.</li>
|
||||
<li>Supports hex, decimal, and binary input and output almost everywhere.
|
||||
(disassembly is still hex)</li>
|
||||
<li>Support for bank switching. You can see how many banks a cart has,
|
||||
and switch banks. There's still more to be done here though.</li>
|
||||
<li>Registers/memory that get changed by the CPU during debugging are
|
||||
highlighted when they're displayed.<li>
|
||||
<li>Scanline advance (like frame advance, break at beginning
|
||||
of next scanline).</li>
|
||||
<li>TIA display is updated during step/trace, so we can see our
|
||||
scanlines being drawn as it happens. This isn't 100% perfect: unlike
|
||||
a real TIA, the one in Stella only updates when it's written to.</li>
|
||||
<li>Graphical TIA tab, with register names and GUI buttons for
|
||||
various bits (e.g. click ENAM0 to turn it on).</li>
|
||||
<li>GUI Disassembly window, scrollable, with checkboxes for breakpoints.</li>
|
||||
<li>Script (batch) file support, including auto-running a script file
|
||||
named after the ROM image.</li>
|
||||
<li>Saving the current debugger state to a script file (including
|
||||
breakpoints, traps, etc).</li>
|
||||
<li>Built-in functions for use with "breakif", to support common conditions
|
||||
(such as breaking when the user presses Game Select...)</li>
|
||||
<li>Patching ROM in-place.</li>
|
||||
<li>Save patched ROM ("saverom filename.bin").</li>
|
||||
</ul>
|
||||
|
||||
<h2>Future planned features (post 2.0):</h2>
|
||||
|
||||
<ul>
|
||||
<li>GUI for cheat codes (Cheetah and normal codes).</li>
|
||||
<li>Perhaps 2 panes in the disassembly window (so you can see 2 parts of the
|
||||
code at once).</li>
|
||||
<li>Add bookmark support to disassembly window.</li>
|
||||
<li>Bankswitch support in the debugger for the few remaining cart types
|
||||
that aren't supported.</li>
|
||||
<li>Patch ROM support for a few cart types doesn't work. Must fix.</li>
|
||||
<li>Some way to control joystick/etc. input from within the debugger.</li>
|
||||
<li>Source-level debugging: if a DASM .lst file is available, we'll show
|
||||
the listing in the ROM tab instead of a disassembly. This is already
|
||||
available in a very crude form ("loadlist" and "list" commands).</li>
|
||||
<li>More "special variables" for the expression parser. Currently, you can
|
||||
use all the CPU registers and flags in expressions (e.g. "print a+1" does
|
||||
what you expect), and the pseudo-variables "_scan" and "_bank" (which
|
||||
evaluate the the current scanline and bank number). Need to add more TIA,
|
||||
RIOT registers too. Also, more functions for the builtin function lib.</li>
|
||||
<li>Possibly a mini-assembler</li>
|
||||
<li>Support for extra RAM in Supercharger and other cart types.</li>
|
||||
<li>Possibly support for recording and playing back input files, like
|
||||
MAME. This isn't a debugger feature per se, but it'll make it easier
|
||||
to reliably trigger a bug so you can debug it.</li>
|
||||
<li>Graphics ROM view, so you can see your sprite data (it might still
|
||||
be upside-down though :)</li>
|
||||
<li>Various new GUI enhancements</li>
|
||||
</ul>
|
||||
|
||||
<h2>How to use the debugger</h2>
|
||||
|
||||
<p>Pressing ` (aka backtick, backquote, grave accent) toggles the debugger on
|
||||
& off. When you exit the debugger, the emulation resumes at the current
|
||||
program counter, and continues until either a breakpoint/trap is hit,
|
||||
or the ` key is pressed again. Pressing Ctrl-Tab cycles between tabs
|
||||
from left to right, and Shift-Ctrl-Tab cycles from right to left.
|
||||
Pressing Tab cycles between widgets in the current tab.</p>
|
||||
|
||||
<p>You can also enter the debugger by giving a breakpoint on the command line:
|
||||
<pre>
|
||||
; will enter the debugger the first time the instruction at "kernel" runs
|
||||
stella -break kernel mygame.bin
|
||||
|
||||
; $fffc is the 6502/6507 init vector. This command will break and enter the
|
||||
; debugger before the first 6507 instruction runs, so you can debug the
|
||||
; startup code:
|
||||
stella -break "*($fffc)" mygame.bin
|
||||
</pre>
|
||||
</p>
|
||||
|
||||
<h2>Prompt tab</h2>
|
||||
|
||||
<p>This is a command-line interface, similar to the DOS DEBUG command
|
||||
or Supermon for the C=64. It shows you the current CPU state, including
|
||||
the disassembly of the instruction pointed to by the Program Counter.
|
||||
This instruction is the NEXT one that will execute, NOT the one that
|
||||
just executed!</p>
|
||||
|
||||
<p>Editing keys work about like you'd expect them to: Home, End, Delete,
|
||||
arrows, etc. To scroll with the keyboard, use Shift-PageUp and
|
||||
Shift-PageDown or Shift-Up and Shift-Down arrow keys. You can also
|
||||
scroll with the mouse. Copy and paste is not (yet?) supported.</p>
|
||||
|
||||
<p>To see the available commands, enter "help" or "?". Most commands can
|
||||
be abbreviated: instead of "clearbreaks", you can type "clear" or
|
||||
even just "cl". However, "c" by itself is the Toggle Carry command.</p>
|
||||
|
||||
<p>Bash-style tab completion is supported for commands and labels (see below)</p>
|
||||
|
||||
<p>For now, there are some functions that only exist in the prompt. We
|
||||
intend to add GUI equivalents for all (or almost all?) of the prompt
|
||||
commands by the time we release Stella 2.0. People who like command
|
||||
prompts will be able to use the prompt, but people who hate them will
|
||||
have a fully functional debugger without typing (or without typing
|
||||
much, anyway).</p>
|
||||
|
||||
<h4>Status</h4>
|
||||
|
||||
<p>Before each prompt, you'll see a dump of the current processor
|
||||
status, plus any watches you've set (see section on watches
|
||||
below), plus a disassembly of the instruction at the current
|
||||
Program Counter. This is the next instruction that will execute;
|
||||
it hasn't been executed yet.</p>
|
||||
|
||||
<pre>
|
||||
PC=f000 A=01 X=02 Y=03 S=ff P=21/nv-bdizC Cycle 12345
|
||||
$f000 a2 ff LDX #ff ; 2
|
||||
>
|
||||
</pre>
|
||||
|
||||
<p>This is telling us a lot of information:
|
||||
<pre>
|
||||
- PC=f000 A=01 X=02 Y=03 S=ff
|
||||
The Program Counter, Accumulator, X, Y, and Stack Pointer registers.
|
||||
|
||||
- P=21/nv-bdizC
|
||||
The Processor Status register. The "21" is the hex value of the
|
||||
register, and the "nv-bdizC" shows us the individual flags. Flags
|
||||
with capital letters are set, and lowercase means clear. In this
|
||||
example, only the Carry bit is set.
|
||||
|
||||
- Cycle 12345
|
||||
This counter gets reset at the beginning of each frame, when
|
||||
VSYNC is strobed. In this example, we're 12345 (decimal) cycles
|
||||
past the beginning of the frame.
|
||||
|
||||
- $f000 a2 ff LDX #ff ; 2
|
||||
Disassembly of the instruction the PC points to. This is the next
|
||||
instruction that will execute (when we exit the debugger, or via the
|
||||
"step" or "trace" commands). The "a2 ff" is the raw machine code
|
||||
for this instruction. The "; 2" is a cycle count: this instruction
|
||||
will take 2 cycles to execute.
|
||||
|
||||
WARNING: the cycle count in the disassembly does NOT include extra
|
||||
cycles caused by crossing page boundaries. Also, Branch instructions
|
||||
are shown as 2 cycles, as though they're not going to be taken. A
|
||||
branch that's taken adds a cycle, of course.
|
||||
|
||||
The ">" is where your commands will appear as you type them.
|
||||
</pre>
|
||||
|
||||
<h4>Tab completion</h4>
|
||||
|
||||
<p>While entering a command or label, you can type a partial name and
|
||||
press the Tab key to attempt to auto-complete it. If you've ever used
|
||||
"bash", this will be immediately familiar. If not, try it: load up
|
||||
a ROM, go to the debugger, type "print w" (but don't press Enter),
|
||||
then hit Tab. The "w" will change to "WSYNC" (since this is the only
|
||||
built-in label starting with a "w"). If there are multiple possible
|
||||
completions (try with "v" instead of "w"), you'll see a list of them,
|
||||
and your partial name will be completed as far as possible.</p>
|
||||
|
||||
<p>Tab completion works on all labels: built-in, loaded from a symbol file,
|
||||
or set during debugging with the "define" command. However, it does not
|
||||
yet work on functions defined with the "function" command, nor does it
|
||||
work on filenames.</p>
|
||||
|
||||
<h4>Expressions</h4>
|
||||
|
||||
<p>Almost every command takes a value: the "a" command takes a
|
||||
byte to stuff into the accumulator, the "break" command
|
||||
takes an address to set/clear a breakpoint at. These values
|
||||
can be as a hex constant ($ff, $1234), or as complex as
|
||||
"the low byte of the 16-bit value located at the address
|
||||
pointed to by the binary number 1010010110100101" (which
|
||||
would be "@<\1010010110100101"). You can also use registers
|
||||
and labels in expressions.</p>
|
||||
|
||||
<p>You can use arithmetic and boolean operators in expressions. The
|
||||
syntax is very C-like. The operators supported are:</p>
|
||||
|
||||
<pre>
|
||||
+ - * / (add, subtract, multiply, divide: 2+2 is 4)
|
||||
% (modulus/remainder: 3%2 is 1)
|
||||
& | ^ ~ (bitwise AND, OR, XOR, NOT: 2&3 is 2)
|
||||
&& || ! (logical AND, OR, NOT: 2&&3 is 1, 2||0 is 0)
|
||||
( ) (parentheses for grouping: (2+2)*3 is 12)
|
||||
* @ (byte and word pointer dereference: *$80 is the byte stored
|
||||
at location $80)
|
||||
[ ] (array-style byte pointer dereference: $80[1] is the byte
|
||||
stored at location ($80+1) or $81)
|
||||
< > (prefix versions: low and high byte. <$abcd is $cd)
|
||||
== < > <= >= !=
|
||||
(comparison: equality, less-than, greater-than, less-or-equals,
|
||||
greater-or-equals, not-equals)
|
||||
<< >> (bit shifts, left and right: 1<<1 is 2, 2>>1 is 1)
|
||||
</pre>
|
||||
|
||||
<p>Division by zero is not an error: it results in zero instead.</p>
|
||||
|
||||
<p>None of the operators change the values of their operands. There
|
||||
are no variable-assignment or increment/decrement operators. This
|
||||
may change in the future, which is why we used "==" for equality
|
||||
instead of just "=".</p>
|
||||
|
||||
<p>The bitwise and logical boolean operators are different in that the
|
||||
bitwise operators operate on all the bits of the operand (just like
|
||||
AND, ORA, EOR in 6502 asm), while the logical operators treat their
|
||||
operands as 0 for false, non-zero for true, and return either 0 or 1.
|
||||
So $1234&$5678 results in $1230, whereas $1234&&$5678 results in 1.
|
||||
This is just like C or C++...</p>
|
||||
|
||||
<h4>Prefixes</h4>
|
||||
|
||||
<p>Like some programming languages, the debugger uses prefixed characters
|
||||
to change the meaning of an expression. The prefixes are:</p>
|
||||
|
||||
<ul>
|
||||
<li>Dereference prefixes:<br>
|
||||
|
||||
<p>"*"<br>
|
||||
Dereference a byte pointer. "*a" means "the byte at the address that
|
||||
the A register points to". If A is 255 (hex $ff), the result will be
|
||||
the value currently stored in memory location 255. This operator
|
||||
will be very familiar to you if you're a C or C++ programmer. It's
|
||||
equivalent to the PEEK() function in most 8-bit BASICs. Also, the
|
||||
debugger supports array-like byte dereferences: *address can be
|
||||
written as address[0]. *(address+1) can be written as address[1],
|
||||
etc.</p>
|
||||
|
||||
<p>"@"<br>
|
||||
Dereference a pointer to a word. This is just like the "*" byte deref,
|
||||
except it refers to a 16-bit value, occupying 2 locations, in
|
||||
low-byte-first format (standard for the 6507).</p>
|
||||
|
||||
<p>The following are equivalent:</p>
|
||||
<pre>
|
||||
@address
|
||||
*address+$100**(address+1)
|
||||
address[0]+#256*address[1]
|
||||
</pre>
|
||||
|
||||
<p>(TODO: add (indirect),y and (indirect,x) syntax)</p>
|
||||
</li>
|
||||
|
||||
<li>Hi/Lo Byte Prefixes:<br>
|
||||
<p>"<"<br>
|
||||
Take the low byte of a 16-bit value. This has no effect on an 8-bit
|
||||
value: "a" is equal to "<a". However, "<$1234" equals "$34".</p>
|
||||
|
||||
<p>">"<br>
|
||||
Take the high byte of a 16-bit value. For 8-bit values such as
|
||||
the Accumulator, this will always result in zero. For 16-bit values,
|
||||
"<$1234" = "$12".</p>
|
||||
</li>
|
||||
|
||||
<li>Number Base Prefixes:<br>
|
||||
<p>"#"<br>
|
||||
Treat the input as a decimal number.</p>
|
||||
|
||||
<p>"$"<br>
|
||||
Treat the input as a hex number.</p>
|
||||
|
||||
<p>"\"<br>
|
||||
Treat the input as a binary number.</p>
|
||||
|
||||
<p>These only have meaning when they come before a number, not a
|
||||
label or a register. "\1010" means 10 decimal. So do "$0a" and
|
||||
"#10". "a" by itself is always the Accumulator, no matter what
|
||||
the default base is set to.</p>
|
||||
|
||||
<p>If you don't specify any number base prefix, the number is
|
||||
assumed to be in the default base. When you first start Stella,
|
||||
the default base is 16 (hexadecimal). You can change it with the
|
||||
"base" command.</p>
|
||||
|
||||
<p>Remember, you can use arbitrarily complex expressions with any
|
||||
command that takes arguments (except the ones that take filenames,
|
||||
like "loadsym").</p>
|
||||
</li>
|
||||
</ul>
|
||||
|
||||
|
||||
<h3>Breakpoints, watches and traps, oh my!</h3>
|
||||
|
||||
<h4>Breakpoints</h4>
|
||||
|
||||
<p>A breakpoint is a "hotspot" in your program that causes the emulator
|
||||
to stop emulating and jump into the debugger. You can set as many
|
||||
breakpoints as you like. The command is "break xx" where xx is any
|
||||
expression. If you've created a symbol file, you can use labels.</p>
|
||||
|
||||
<p>Example: you've got a label called "kernel". To break there,
|
||||
the command is "break kernel". After you've set the breakpoint,
|
||||
exit the debugger ("quit" or click the Exit button). The emulator
|
||||
will run until it gets to the breakpoint, then it will enter the
|
||||
debugger with the Program Counter pointing to the instruction
|
||||
at the breakpoint.</p>
|
||||
|
||||
<p>Breakpoints happen *before* an instruction is executed: the
|
||||
instruction at the breakpoint location will be the "next"
|
||||
instruction.</p>
|
||||
|
||||
<p>To remove a breakpoint, you just run the same command you used to
|
||||
set it. In the example, "break kernel" will remove the breakpoint.
|
||||
The "break" command can be thought of as a *toggle*: it turns the
|
||||
breakpoint on & off, like a light switch.</p>
|
||||
|
||||
<p>You could also use "clearbreaks" to remove all the breakpoints. Also,
|
||||
there is a "listbreaks" command that will list them all.</p>
|
||||
|
||||
<h4>Conditional Breaks</h4>
|
||||
|
||||
<p>A conditional breakpoint causes the emulator to enter the debugger when
|
||||
some arbitrary condition becomes true. "True" means "not zero" here:
|
||||
"2+2" is considered true because it's not zero. "2-2" is false, because
|
||||
it evaluates to zero. This is exactly how things work in C and lots
|
||||
of other languages, but it might take some getting used to if you've
|
||||
never used such a language.</p>
|
||||
|
||||
<p>Suppose you want to enter the debugger when the Game Reset switch is
|
||||
pressed. Looking at the Stella Programmers' Guide, we see that this
|
||||
switch is read at bit 0 of SWCHB. This bit will be 0 if the switch is
|
||||
pressed, or 1 otherwise.</p>
|
||||
|
||||
<p>To have an expression read the contents of an address, we use the
|
||||
dereference operator "*". Since we're looking at SWCHB, we need
|
||||
"*SWCHB".</p>
|
||||
|
||||
<p>We're only wanting to look at bit 0, so let's mask off all the other
|
||||
bits: "*SWCHB&1". The expression now evaluates to bit 0 of SWCHB. We're
|
||||
almost there: this will be 1 (true) if the switch is NOT pressed. We
|
||||
want to break if it IS pressed...</p>
|
||||
|
||||
<p>So we invert the sense of the test with a logical NOT operator (which
|
||||
is the "!" operator): !(*SWCHB&1). The parentheses are necessary as
|
||||
we want to apply the ! to the result of the &, not just the first term
|
||||
(the "*SWCHB").</p>
|
||||
|
||||
<p>"breakif !(*SWCHB&1)" will do the job for us. However, it's an ugly mess
|
||||
of letters, numbers, and punctuation. We can do a little better:</p>
|
||||
|
||||
<p>"breakif { !(*SWCHB & 1 ) }" is a lot more readable, isn't it? If
|
||||
you're going to use readable expressions with spaces in them,
|
||||
enclose the entire expression in curly braces {}.</p>
|
||||
|
||||
<p>There is one annoyance about this complex expression: once we
|
||||
remove the conditional break with "delbreakif" or "clearbreaks",
|
||||
we'd have to retype it (or search backwards with the up-arrow key)
|
||||
if we wanted to use it again.</p>
|
||||
|
||||
<p>We can avoid this by defining the expression as a function, then using
|
||||
"breakif function_name":</p>
|
||||
|
||||
<pre>
|
||||
function gameReset { !(*SWCHB & 1 ) }
|
||||
breakif gameReset
|
||||
</pre>
|
||||
|
||||
<p>Now we have a meaningful name for the condition, so we can use it again.
|
||||
Not only that: we can use the function as part of a bigger expression.
|
||||
Suppose we've also defined a gameSelect function that evaluates to true
|
||||
if the Game Select switch is pressed. We want to break when the user
|
||||
presses both Select and Reset:</p>
|
||||
|
||||
<pre>
|
||||
breakif { gameReset && gameSelect }
|
||||
</pre>
|
||||
|
||||
<p>If you've defined a lot of complex functions, you probably will
|
||||
want to re-use them in future runs of the debugger. You can save
|
||||
all your functions, breakpoints, conditional breaks, and watches
|
||||
with the "save" command. If you name your saved file the same
|
||||
as the ROM filename, it'll be auto-loaded next time you load the
|
||||
same ROM in Stella. The save file is just a plain text file called
|
||||
"filename.stella", so you can edit it and add new functions, etc.</p>
|
||||
|
||||
<p>Conditional breaks appear in "listbreaks", numbered starting from
|
||||
zero. You can remove a cond. break with "delbreakif number", where
|
||||
the number comes from "listbreaks".</p>
|
||||
|
||||
<h4>Watches</h4>
|
||||
|
||||
<p>A watch is an expression that gets evaluated and printed before
|
||||
every prompt. This is useful for e.g. tracking the contents of a
|
||||
memory location while stepping through code that modifies it.</p>
|
||||
|
||||
<p>You can set up to 10 watches (in future the number will be unlimited).
|
||||
Since the expression isn't evaluated until it's used, you can include
|
||||
registers: "watch *y" will show you the contents of the location
|
||||
pointed to by the Y register, even if the Y register changes.</p>
|
||||
|
||||
<p>The watches are numbered. The numbers are printed along with the
|
||||
watches, so you can tell which is which. To delete a watch use the
|
||||
"delwatch" command with the watch number (1 to whatever). You can
|
||||
also delete them all with the "clearwatches" command.</p>
|
||||
|
||||
<p>Note that there's no real point in watching a label or CPU register
|
||||
without dereferencing it: Labels are constants, and CPU registers
|
||||
are already visible in the prompt status.</p>
|
||||
|
||||
<h4>Traps</h4>
|
||||
|
||||
<p>A trap is similar to a breakpoint, except that it catches
|
||||
accesses to a memory address, rather than specific location in the
|
||||
program. They're useful for finding code that modifies TIA registers
|
||||
or memory.</p>
|
||||
|
||||
<p>An example: you are debugging a game, and you want to stop the
|
||||
emulation and enter the debugger whenever RESP0 is strobed. You'd use
|
||||
the command "trap RESP0" to set the trap, then exit the debugger. The
|
||||
emulator will run until the next time RESP0 is accessed (either read
|
||||
or write). Once the trap is hit, you can examine the TIA state to
|
||||
see what the actual player 0 position is, in color clocks (or you
|
||||
can in the future when we implement that feature in the TIA dump!)</p>
|
||||
|
||||
<p>Unlike breakpoints, traps stop the emulation *after* the instruction
|
||||
that triggered the trap. The reason for this is simple: until the
|
||||
instruction is executed, the emulator can't know it's going to hit
|
||||
a trap. After the trap is hit, the instruction is done executing,
|
||||
and whatever effects it may have had on e.g. the TIA state have
|
||||
already happened... so we don't have a way to run the emulated CPU
|
||||
in reverse.</p>
|
||||
|
||||
<p>Traps come in two varieties: read access traps and write access traps.
|
||||
It is possible to set both types of trap on the same address (that's
|
||||
what the plain "trap" command does). To set a read or write only trap,
|
||||
use "trapread" or "trapwrite". To remove a trap, you just attempt
|
||||
to set it again: the commands actually toggle the trap on & off. You
|
||||
can also get rid of all traps at once with the "cleartraps" command.</p>
|
||||
|
||||
<p>Use "listtraps" to see all enabled traps.</p>
|
||||
|
||||
<h3>Prompt commands:</h3>
|
||||
|
||||
<pre>
|
||||
a - Set Accumulator to value xx
|
||||
bank - Show # of banks (with no args), Switch to bank (with
|
||||
1 arg)
|
||||
base - Set default base (hex, dec, or bin)
|
||||
break - Set/clear breakpoint at address (default=pc)
|
||||
c - Carry Flag: set (to 0 or 1), or toggle (no arg)
|
||||
clearbreaks - Clear all breakpoints
|
||||
cleartraps - Clear all traps
|
||||
clearwatches - Clear all watches
|
||||
colortest - Color Test
|
||||
d - Decimal Flag: set (to 0 or 1), or toggle (no arg)
|
||||
define - Define label
|
||||
delwatch - Delete watch
|
||||
disasm - Disassemble from address (default=pc)
|
||||
dump - Dump 128 bytes of memory at address
|
||||
frame - Advance emulation by xx frames (default=1)
|
||||
help - This cruft
|
||||
listbreaks - List breakpoints
|
||||
listtraps - List traps
|
||||
listwatches - List watches
|
||||
loadstate - Load emulator state (0-9)
|
||||
loadsym - Load symbol file
|
||||
n - Negative Flag: set (to 0 or 1), or toggle (no arg)
|
||||
pc - Set Program Counter to address
|
||||
print - Evaluate and print expression in hex/dec/binary
|
||||
ram - Show RAM contents (no args), or set RAM address xx to
|
||||
value yy
|
||||
reload - Reload ROM and symbol file
|
||||
reset - Reset 6507 to init vector (does not reset TIA, RIOT)
|
||||
riot - Show RIOT timer/input status
|
||||
rom - Change ROM contents
|
||||
run - Exit debugger, return to emulator
|
||||
s - Set Stack Pointer to value xx
|
||||
saveses - Save console session to file
|
||||
savestate - Save emulator state (valid args 0-9)
|
||||
savesym - Save symbols to file
|
||||
step - Single step CPU (optionally, with count)
|
||||
tia - Show TIA state
|
||||
trace - Single step CPU (optionally, with count), subroutines
|
||||
count as one instruction
|
||||
trap - Trap read and write accesses to address
|
||||
trapread - Trap read accesses to address
|
||||
trapwrite - Trap write accesses to address
|
||||
undef - Undefine label (if defined)
|
||||
v - Overflow Flag: set (to 0 or 1), or toggle (no arg)
|
||||
watch - Print contents of address before every prompt
|
||||
x - Set X Register to value xx
|
||||
y - Set Y Register to value xx
|
||||
z - Zero Flag: set (to 0 or 1), or toggle (no arg)
|
||||
|
||||
</pre>
|
||||
<p>This list may be outdated: see the output of the "help" command
|
||||
for the current list. Commands marked with a * are unimplemented.
|
||||
Commands marked with a + are partially implemented. Most commands can
|
||||
be abbreviated just by typing a partial command: "st" for "step", or
|
||||
"f" for "frame". Where there are conflicts, generally the shortest
|
||||
name is chosen (so "tra" is "trap", not "trapread").</p>
|
||||
|
||||
|
||||
<h2>CPU Widget</h2>
|
||||
|
||||
<p>FIXME: document this</p>
|
||||
|
||||
|
||||
<h2>RAM Widget</h2>
|
||||
|
||||
<p>This is a spreadsheet-like GUI for inspecting and changing the contents
|
||||
of the 2600's RAM. All 128 bytes of RAM are visible on the screen at
|
||||
once. You can navigate with either the mouse or the keyboard arrow keys.
|
||||
To change a RAM location, either double-click on it or press Enter while
|
||||
it's highlighted. Enter the new value (hex only for now, sorry), then
|
||||
press Enter to make the change. If you change your mind, press Escape
|
||||
and the original value will be restored.</p>
|
||||
|
||||
<p>Nearby there are also some buttons to do various things to the
|
||||
currently-selected memory location. The buttons are:</p>
|
||||
|
||||
<pre>
|
||||
0 - Set the current location to zero.
|
||||
Inv - Invert the current location (toggle all its bits).
|
||||
Neg - Negate the current location (twos' complement negative).
|
||||
++ - Increment the current location
|
||||
-- - Decrement the current location
|
||||
<< - Shift the current location left. Any bits shifted off the left
|
||||
are lost (they will NOT end up in the Carry flag).
|
||||
>> - Shift the current location right, like << above.
|
||||
</pre>
|
||||
|
||||
<p>This widget also lets you search memory for values such as lives or remaining
|
||||
energy, but it's also very useful when debugging to determine which
|
||||
memory location holds which quantity.</p>
|
||||
|
||||
<p>To search RAM, click 'Search' and enter a byte value into the search editbox (0-255).
|
||||
All matching values will be highlighted in the RAM widget. If 'Search' is clicked
|
||||
and input is empty, all RAM locations are searched.</p>
|
||||
|
||||
<p>The 'Compare' button is used to compare the given value using all
|
||||
addresses currently highlighted. This may be an absolute number (such as 2),
|
||||
or a comparitive number (such as -1). Using a '+' or '-' operator
|
||||
means 'search addresses for values that have changed by that amount'.</p>
|
||||
|
||||
<p>The following is an example of inspecting all addresses that have
|
||||
decreased by 1:
|
||||
|
||||
<ul>
|
||||
<li>Click 'Search' with empty input. All 128 address/values are highlighted</li>
|
||||
<li>Exit debugger mode and lose a life, let your energy decrease, or
|
||||
do whatever it is you're trying to debug</li>
|
||||
<li>Enter debugger mode again, click 'Compare' and and enter a '-1' for input.
|
||||
This finds all values that have decreased by 1 (as compared to their current
|
||||
values)</li>
|
||||
<li>Repeatedly following these steps may help to narrow number of
|
||||
addresses under consideration, and eventually you'll find the
|
||||
memory address you're looking for</li>
|
||||
<li>The 'Reset' button restarts the whole procedure (ie, clear the highlighted
|
||||
addresses and allow another search</li>
|
||||
</ul>
|
||||
|
||||
<h2>TIA Tab</h2>
|
||||
|
||||
<p>FIXME</p>
|
||||
|
||||
<h2>ROM Widget</h2>
|
||||
|
||||
<p>FIXME</p>
|
||||
|
||||
<h2>Global Buttons</h2>
|
||||
|
||||
<p>There are also buttons on the right that always show up no matter which
|
||||
tab you're looking at. These are always active. They are: Step, Trace,
|
||||
Frame+1, Scan+1 and Exit.</p>
|
||||
|
||||
<p>When you use these buttons, the prompt doesn't change. This means the
|
||||
status lines with the registers and disassembly will be "stale". You
|
||||
can update them just by pressing Enter in the prompt.</p>
|
||||
|
||||
<p>You can also use the Step, Trace, Frame+1 and Scan+1 buttons from anywhere in
|
||||
the GUI via the keyboard, with Alt-S, Alt-T, Alt-F and Alt-L.</p>
|
||||
|
||||
|
||||
<h2>Tutorial: How to hack a ROM</h2>
|
||||
|
||||
<p>Here is a step-by-step guide that shows you how to use the debugger to
|
||||
actually do something useful. No experience with debuggers is necessary,
|
||||
but it helps to know at least a little about 6502 programming.</p>
|
||||
|
||||
<ol>
|
||||
<li>get the Atari Battlezone ROM image. Make sure you've got the
|
||||
regular NTSC version. Load it up in Stella and press TAB to get to
|
||||
the main menu. From there, click on "Game Information". For "Name", it
|
||||
should say "Battlezone (1983) (Atari) [!]" and for MD5Sum it should say
|
||||
"41f252a66c6301f1e8ab3612c19bc5d4". The rest of this tutorial assumes
|
||||
you're using this version of the ROM; it may or may not work with the
|
||||
PAL version, or with any of the various "hacked" versions floating around
|
||||
on the 'net.</li>
|
||||
|
||||
<li>Start the game. You begin the game with 5 lives (count the tank
|
||||
symbols at the bottom of the screen).</li>
|
||||
|
||||
<li>Enter the debugger by pressing the ` (backquote) key. Don't get
|
||||
killed before you do this, though. You should still have all 5 lives.</li>
|
||||
|
||||
<li>In the RAM Widget, click the "Search" button and enter "5" for input.
|
||||
This searches RAM for your value and highlights all addresses that match
|
||||
the input. You should see two addresses highlighted: "00a5" and "00ba".
|
||||
These are the only two addresses that currently have the value 5, so they're
|
||||
the most likely candidates for "number of lives" counter. (However, some
|
||||
games might actually store one less than the real number of lives, or
|
||||
one more, so you might have to experiment a bit. Since this is a "rigged
|
||||
demo", I already know Battlezone stores the actual number of lives.
|
||||
Most games do, actually).</li>
|
||||
|
||||
<li>Exit the debugger by pressing ` (backquote) again. The game will
|
||||
pick up where you left off.</li>
|
||||
|
||||
<li>Get killed! Ram an enemy tank, or let him shoot you. Wait for
|
||||
the explosion to finish. You will now have 4 lives.</li>
|
||||
|
||||
<li>Enter the debugger again. Click the "Compare" button in RAM widget and enter
|
||||
a value of 4. Now the RAM widget should only show one highlighted address:
|
||||
"00ba". What we did was search within our previous results (the ones that
|
||||
were 5 before) for the new value 4. Address $00ba used to have the value 5,
|
||||
but now it has 4. This means that Battlezone (almost certainly) stores the
|
||||
current number of lives at address $00ba.</li>
|
||||
|
||||
<li>Test your theory. Go to the RAM widget and change address $ba to
|
||||
some high number like $ff (you could use the Prompt instead: enter "ram
|
||||
$ba $ff"). Exit the debugger again. You should now see lots of lives
|
||||
at the bottom of the screen (of course, there isn't room to display $ff
|
||||
(255) of them!)... play the game, get killed a few times, notice that
|
||||
you have lots of lives.</li>
|
||||
|
||||
<li>Now it's time to decide what sort of "ROM hack" we want to
|
||||
accomplish. We've found the "lives" counter for the game, so we can
|
||||
either have the game start with lots of lives, or change the game
|
||||
code so we can't get killed (AKA immortality), or change the code
|
||||
so we always have the same number of lives (so we never run out, AKA
|
||||
infinite lives). Let's go for infinite lives: it's a little harder than
|
||||
just starting with lots of lives, but not as difficult as immortality
|
||||
(for that, we have to disable the collision checking code, which means
|
||||
we have to find and understand it first!)</li>
|
||||
|
||||
<li>Set a Write Trap on the lives counter address: "trapwrite $ba"
|
||||
in the Prompt. Exit the debugger and play until you get killed. When
|
||||
you die, the trap will cause the emulator to enter the debugger with the
|
||||
Program Counter pointing to the instruction *after* the one that wrote
|
||||
to location $ba.</li>
|
||||
|
||||
<li>Once in the debugger, look at the ROM widget. The PC should be at address
|
||||
$f238, instruction "LDA $e1". You want to examine a few instructions before
|
||||
the PC, so scroll up using the mouse or arrow keys. Do you see
|
||||
the one that affects the lives counter? That's right, it's the "DEC $ba"
|
||||
at location $f236.</li>
|
||||
|
||||
<li>Let's stop the DEC $ba from happening. We can't just delete the
|
||||
instruction (it would mess up the addressing of everything afterwards,
|
||||
if it were even possible), but we can replace it with some other
|
||||
instruction(s).
|
||||
|
||||
<p>Since we just want to get rid of the instruction, we can replace it with
|
||||
NOP (no operation). From looking at the disassembly, you can see that
|
||||
"DEC $ba" is a 2-byte long instruction, so we will need two one-byte
|
||||
NOP instructions to replace it. From reading the prompt help (the "help"
|
||||
command), you can see that the "rom" command is what we use to patch ROM.
|
||||
|
||||
<p>Unfortunately, Stella doesn't contain an assembler, so we can't just
|
||||
type NOP to put a NOP instruction in the code. We'll have to use the
|
||||
hex opcode instead.
|
||||
|
||||
<p>Now crack open your 6502 reference manual and look up the NOP
|
||||
instruction's opcode... OK, OK, I'll just tell you what it is: it's $EA
|
||||
(234 decimal). We need two of them, so the bytes to insert will look like:
|
||||
|
||||
<pre> $ea $ea</pre>
|
||||
|
||||
<p>Select the line at address $f236 and enter 'ROM patch' mode. This is done
|
||||
by either double-clicking the line, or pressing enter. Then delete the bytes
|
||||
with backspace key and enter "ea ea". Another way to do this would have been
|
||||
to enter "rom $f236 $ea $ea" in the Prompt widget.
|
||||
</li>
|
||||
|
||||
<li>Test your patch. First, set location $ba to some number of
|
||||
lives that can be displayed on the screen ("poke $ba 3" or enter directly into
|
||||
the RAM widget). Now exit the debugger and play the game. You should see 3
|
||||
lives on the screen.</li>
|
||||
|
||||
<li>The crucial test: get killed again! After the explosion, you
|
||||
will *still* see 3 lives: Success! We've hacked Battlezone to give us
|
||||
infinite lives.</li>
|
||||
|
||||
<li>Save your work. In the prompt: "saverom bzhack.bin". You now
|
||||
have your very own infinite-lives version of Battlezone. The file will
|
||||
be saved in the current directory (NOT your ROM directory), so you might
|
||||
want to move it to your ROM directory if it isn't the current directory.
|
||||
This can also be accomplished by right-clicking on the ROM widget and
|
||||
selected 'Save ROM'.</li>
|
||||
|
||||
<li>Test the new ROM: exit Stella, and re-run it. Open your ROM
|
||||
(or give its name on the command line) and play the game. You can play
|
||||
forever! It worked.</li>
|
||||
</ol>
|
||||
|
||||
<p>Now, try the same techniques on some other ROM image (try Pac-Man). Some
|
||||
games store (lives+1) or (lives-1) instead of the actual number,
|
||||
so try searching for those if you can't seem to make it work. Also,
|
||||
some cartridge types include their own RAM. The debugger doesn't (yet)
|
||||
know how to access on-cartridge RAM, so you'll have to use the "bank" and
|
||||
"ram" commands to manually search the address space for the value you're
|
||||
looking for (future versions of the debugger will be smarter about this).</p>
|
||||
|
||||
<p>If you successfully patch a ROM in the debugger, but the saved version
|
||||
won't work, or looks funny, you might need to add an entry to the
|
||||
stella.pro file, to tell Stella what bankswitch and/or TV type to use.
|
||||
That's outside the scope of this tutorial :)</p>
|
||||
|
||||
<p>Of course, the debugger is useful for a lot more than cheating and
|
||||
hacking ROMs. Remember, with great power comes great responsibility,
|
||||
so you have no excuse to avoid writing that game you've been thinking
|
||||
about for so long now :)</p>
|
||||
|
|
@ -35,7 +35,7 @@
|
|||
|
||||
<br><br><br>
|
||||
|
||||
<center><b>February 1999 - (FIXME)February 2005</b></center>
|
||||
<center><b>February 1999 - September 2005</b></center>
|
||||
<center><b>The Stella Team</b></center>
|
||||
<center><b><a href="http://stella.sourceforge.net">Stella Homepage</a></b></center>
|
||||
|
||||
|
|
@ -230,14 +230,22 @@
|
|||
(the Windows and Linux frontends) have been discontinued. The OSX
|
||||
port now uses the launcher as well.</li>
|
||||
|
||||
<li>FIXME - add info about integrated debugger</li>
|
||||
<li>Added an integrated debugger for game developers. This is currently
|
||||
the first version of a debugger in Stella, but it's already quite
|
||||
usable.</li>
|
||||
|
||||
<li>Further consolidation and integration of SDL. This should lead to
|
||||
faster operation and a more consistent look for all ports.</li>
|
||||
<li>Added new sound subsystem, which is much faster and more accurate. Related
|
||||
to this, added stereo sound output (used by some homebrew games).
|
||||
|
||||
<li>Added ZIP support. Stella can now open ROM's compressed in zip
|
||||
format.</li>
|
||||
|
||||
<li>Reworked properties system to use both a system-wide 'stella.pro' and
|
||||
a per-user 'user.pro' properties files. Changes made by the user
|
||||
and stored in 'user.pro' are no longer erased when upgrading Stella.</li>
|
||||
|
||||
<li>Added support for cartridges with 3E bankswitching format.</li>
|
||||
|
||||
<li>Added <b>Alt/Shift-Cmd z, x, c, v, b, n</b> keys to enable/disable the
|
||||
P0, P1, M0, M1, BL, PL bits in the TIA, respectively.</li>
|
||||
|
||||
|
|
@ -266,15 +274,22 @@
|
|||
<li>Removed <b>mergeprops</b> commandline argument, since there are now
|
||||
dedicated keys to do either save or merge game properties.</li>
|
||||
|
||||
<li>Removed <b>grabmouse</b> and <b>hidecursor</b> commandline arguments.
|
||||
Stella will now automatically decide when to use these settings.
|
||||
You can still use <b>Ctrl/Cmd g</b> to grab/ungrab the mouse.</li>
|
||||
<li>Removed <b>hidecursor</b> commandline argument. Stella will now
|
||||
automatically decide when to use this setting.</li>
|
||||
|
||||
<li>Fixed framerate when switching between NTSC and PAL modes. Stella
|
||||
now uses the correct framerate based on the format of the ROM.</li>
|
||||
now uses the correct framerate based on the format of the ROM,
|
||||
in terms of both video <b>and</b> audio.</li>
|
||||
|
||||
<li>Added 'configure' support to the build process for both Linux and
|
||||
Win32 (using MinGW). Developers can now use the familiar 'configure;
|
||||
make; make install' commands to compile Stella.</li>
|
||||
|
||||
<li>Further consolidation and integration of SDL. This should lead to
|
||||
faster operation and a more consistent look for all ports.</li>
|
||||
|
||||
<li>Fixed some 64-bit issues. Stella now compiles and runs correctly
|
||||
on AMD64 and PPC64 systems.</li>
|
||||
on AMD64 and PPC64 Linux systems.</li>
|
||||
|
||||
<li>Updated the Stella manual with pictures of the new integrated GUI.</li>
|
||||
</ul>
|
||||
|
|
@ -284,8 +299,8 @@
|
|||
|
||||
<ul>
|
||||
<li>High speed emulation using optimized C++ code</li>
|
||||
<li>Supports high quality sound emulation using Ron Fries' TIA Sound Emulation
|
||||
library</li>
|
||||
<li>Supports high quality sound emulation using code derived from Ron Fries'
|
||||
TIA Sound Emulation library, including stereo sound support</li>
|
||||
<li>Emulates the Atari 2600 Joystick Controllers using your computer's keyboard
|
||||
or joysticks</li>
|
||||
<li>Emulates the Atari 2600 Keyboard Controllers using your computer's keyboard</li>
|
||||
|
|
@ -349,7 +364,7 @@
|
|||
<ul>
|
||||
<li>Linux Kernel 2.4.x, Linux Kernel 2.6.x is highly recommended</li>
|
||||
<li>GNU C++ compiler version 2.95 and the make utility are required for compiling
|
||||
the Stella source code; GNU C++ compiler version 3.2.x or later is highly
|
||||
the Stella source code; GNU C++ compiler version 3.2.x/4.x or later is highly
|
||||
recommended</li>
|
||||
<li>Pentium class machine required (Stella <b>may</b> compile on other
|
||||
architectures, but it hasn't been extensively tested)</li>
|
||||
|
|
@ -364,6 +379,8 @@
|
|||
<li>Mac OSX 10.1 or Above</li>
|
||||
<li>500 MHz G4 PPC processor or above (Stella <b>may</b> work with a G3
|
||||
processor, but this is still a work-in-progress)</li>
|
||||
<li>OpenGL capable video card. Software rendering mode is still available,
|
||||
but as of OSX 10.4 is substandard compared to OpenGL.</li>
|
||||
</ul>
|
||||
|
||||
<p>
|
||||
|
|
@ -402,15 +419,14 @@
|
|||
<ol>
|
||||
<li>Extract files from the distribution:
|
||||
<pre> tar zxvf stella-release-src.tar.gz</pre></li>
|
||||
<li>Change directories to the stella-<i>release</i>/src/build directory</li>
|
||||
<li>Edit the <b>makefile</b> to meet your needs</li>
|
||||
<li>Change directories to the stella-<i>release</i> directory</li>
|
||||
|
||||
<li>Configure the build with the following command:
|
||||
<pre> ./configure (--help for list of options)</pre></li>
|
||||
<li>Build the executable with the following command:
|
||||
<pre> make linux (or make linux-gl)</pre></li>
|
||||
<li>Copy the executable to a directory that's in your path:
|
||||
<pre> cp stella /usr/local/bin</pre></li>
|
||||
<li>Copy the supplied stella.pro properties file to the system-wide location:
|
||||
<pre> cp stella.pro /etc</pre> or to your home directory:
|
||||
<pre> mkdir ~/.stella<br> cp stella.pro ~/.stella</pre></li>
|
||||
<pre> make</pre></li>
|
||||
<li>Install the executable with the following command:
|
||||
<pre> make install</pre></li>
|
||||
</ol>
|
||||
<li><b>Source RPM</b> (stella-<i>release</i>-1.src.rpm)</li>
|
||||
<ol>
|
||||
|
|
@ -442,19 +458,11 @@
|
|||
<li>Extract files from the distribution using <b>Winzip</b>,
|
||||
<b>Total Commander</b>, or some other archiving program that supports
|
||||
gzipped tar files</li>
|
||||
<li>If compiling the Stella executable using MinGW:</li>
|
||||
<ul>
|
||||
<li>Change directories to the stella-<i>release</i>/src/build
|
||||
directory</li>
|
||||
<li>Edit the <b>makefile</b> to meet your needs</li>
|
||||
<li>Build the executable with the following command:
|
||||
<pre> make win32 (or make win32-gl)</pre></li>
|
||||
<li>Copy the <b>Stella</b> (commandline executable) and <b>stella.pro</b>
|
||||
files to some directory</li>
|
||||
</ul>
|
||||
<li>If compiling the Stella executable using MinGW, use the same commands
|
||||
as specified under <i>Linux/UNIX - Compressed tarball</i></li>
|
||||
<li>If compiling using Visual C++ 7:</li>
|
||||
<ul>
|
||||
<li>Open the <b>stella-<i>release</i>/src/win32/Stella_Emulator.sln</b>
|
||||
<li>Open the <b>stella-<i>release</i>/src/win32/Stella.sln</b>
|
||||
file using Visual C++ 7</li>
|
||||
<li>Build the 'Stella' solution</li>
|
||||
<li>Copy the <b>Stella.exe</b> and <b>stella.pro</b> files
|
||||
|
|
@ -562,8 +570,8 @@
|
|||
<img src="graphics/rom_browser.png"></p>
|
||||
|
||||
<p>Once a ROM directory has been selected, clicking 'Reload' will update the
|
||||
ROM listing. You can start emulation by selecting a ROM and pressing 'Enter',
|
||||
clicking 'Play' or double-clicking a ROM.</p>
|
||||
ROM listing. You can start emulation by selecting a ROM and pressing 'Enter'
|
||||
or clicking 'Play', or double-clicking a ROM.</p>
|
||||
|
||||
<p>
|
||||
<h2><b>Command Line</b></h2>
|
||||
|
|
@ -589,12 +597,6 @@
|
|||
<td>Use SDL software or OpenGL rendering mode.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-video_driver <windib|directx></pre></td>
|
||||
<td>Use the specified video driver. Windows works best with 'windib'.
|
||||
Currently, only Windows makes use of this argument.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-gl_filter <nearest|linear></pre></td>
|
||||
<td>OpenGL mode only. Use GL_NEAREST or GL_LINEAR filtering.
|
||||
|
|
@ -627,6 +629,11 @@
|
|||
<td>Play the game in fullscreen mode.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-center <0|1></pre></td>
|
||||
<td>Centers game window (if possible).</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-grabmouse <0|1></pre></td>
|
||||
<td>Keeps the mouse in the game window.</td>
|
||||
|
|
@ -645,8 +652,13 @@
|
|||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-sound <0|1></pre></td>
|
||||
<td>Disable or enable sound.</td>
|
||||
<td><pre>-sound <1|0></pre></td>
|
||||
<td>Enable or disable sound generation.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-channels <1|2></pre></td>
|
||||
<td>Enable mono or stereo sound.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
|
|
@ -670,12 +682,6 @@
|
|||
<td>Shows some game info while Stella is running.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-mergeprops <0|1></pre></td>
|
||||
<td>Save the current properties to a separate file in the users' home directory,
|
||||
or merge them into the users' stella.pro file.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-accurate <0|1></pre></td>
|
||||
<td>Linux only, may be removed in future versions. Use this when
|
||||
|
|
@ -723,6 +729,31 @@
|
|||
<th>Description</th>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-debugheight <number></pre></td>
|
||||
<td>Set height of debugger in lines of text (currently not 100% working)</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-debug</pre></td>
|
||||
<td>Immediately jump to debugger mode when starting Stella.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-holdreset</pre></td>
|
||||
<td>Start the emulator with the Game Reset switch held down.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-holdselect</pre></td>
|
||||
<td>Start the emulator with the Game Select switch held down.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-holdbutton0</pre></td>
|
||||
<td>Start the emulator with the left joystick button held down.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><pre>-pro <props file></pre></td>
|
||||
<td>Use the given properties file instead of stella.pro.</td>
|
||||
|
|
@ -1483,7 +1514,7 @@
|
|||
<tr>
|
||||
<td>Toggle fullscreen/windowed mode</td>
|
||||
<td>Alt + Enter</td>
|
||||
<td>Shift-Cmd + Enter(FIXME)</td>
|
||||
<td>Cmd + Enter</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
|
|
@ -1585,7 +1616,9 @@
|
|||
<p><h1>
|
||||
<a name="Debugger">10. Integrated Debugger</a></h1>
|
||||
<hr>
|
||||
FIXME - add info and snapshots for debugger
|
||||
|
||||
<p>Have a look at <a href="debugger.html">this page</a> for integrated debugger
|
||||
documentation.
|
||||
|
||||
<br><br><br>
|
||||
<p><h1>
|
||||
|
|
@ -1597,20 +1630,27 @@ FIXME - add info and snapshots for debugger
|
|||
You must use the included <b>stella.pro</b> file. Otherwise, the emulator
|
||||
will try to guess the best settings for the game.</p>
|
||||
|
||||
<p>As of Stella 2.0, the properties file handling has changed. Stella now uses
|
||||
two properties files; a system-wide <b>stella.pro</b> and a per-user <b>user.pro</b>.
|
||||
The system-wide file will not be modified by Stella, and is used as a default
|
||||
database of properties. The per-user file will contain all properties 'merged' by
|
||||
the user (by pressing Alt-s while a game is running). So this means that when
|
||||
you upgrade Stella and stella.pro, your personal profile settings are preserved.</p>
|
||||
|
||||
<p>
|
||||
<h2><b>Linux/Unix</b></h2>
|
||||
<p>The Linux and Unix versions of Stella looks for the property file
|
||||
in your <i>$HOME/.stella</i> directory. If this file is not found there,
|
||||
Stella will look in the <i>/etc/</i> directory.
|
||||
<p>The Linux and Unix versions of Stella looks for the system properties file
|
||||
in <i>/etc/stella.pro</i> and your personal properties file in
|
||||
<i>$HOME/.stella/user.pro</i>.
|
||||
|
||||
<p>
|
||||
<h2><b>Macintosh</b></h2>
|
||||
<p>The Mac version of Stella looks for the property file in the
|
||||
<p>The Mac version of Stella looks for the properties file(s) in the
|
||||
directory containing the application.</p>
|
||||
|
||||
<p>
|
||||
<h2><b>Windows</b></h2>
|
||||
<p>The Windows version of Stella looks for the property file in the same directory
|
||||
<p>The Windows version of Stella looks for the properties file(s) in the directory
|
||||
containing the application. Future versions of Stella for Windows may look in
|
||||
user-specific locations (C:\Documents and Settings\...).</p>
|
||||
|
||||
|
|
@ -1698,6 +1738,14 @@ FIXME - add info and snapshots for debugger
|
|||
Stella will probably allow the user to view this information.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td VALIGN="TOP"><i>Cartridge.Sound:</i></td>
|
||||
<td>This property determines if the game should use 1 or 2 channels for
|
||||
sound output. All original Atari 2600 machines supported 1 channel only,
|
||||
but some homebrew games have been written to take advantage of stereo
|
||||
sound. The value of this property must be Mono or Stereo.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td VALIGN="TOP"><i>Cartridge.Type:</i></td>
|
||||
<td>This property indicates the bank-switching type for the game.
|
||||
|
|
@ -2028,7 +2076,9 @@ FIXME - add info and snapshots for debugger
|
|||
<td VALIGN="TOP">Brian Watson</td>
|
||||
<td>Helped with getting the illegal CPU instruction support working with Stella.
|
||||
Brian also submitted a number of other changes, such as debugger support, which
|
||||
will be integrated into the 1.5 release of Stella.</td>
|
||||
have been finally integrated into the 2.0 release of Stella. Without
|
||||
a doubt, there would be no debugger support in Stella if not for the
|
||||
tireless work of Brian.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: FrameBufferGL.cxx,v 1.41 2005-09-06 19:42:35 stephena Exp $
|
||||
// $Id: FrameBufferGL.cxx,v 1.42 2005-09-13 18:27:42 stephena Exp $
|
||||
//============================================================================
|
||||
|
||||
#ifdef DISPLAY_OPENGL
|
||||
|
|
@ -254,8 +254,6 @@ void FrameBufferGL::preFrameUpdate()
|
|||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
void FrameBufferGL::postFrameUpdate()
|
||||
{
|
||||
// Do the following twice, since OpenGL mode is double-buffered,
|
||||
// and we need the contents placed in both buffers
|
||||
if(theRedrawTIAIndicator || myDirtyFlag)
|
||||
{
|
||||
// Texturemap complete texture to surface so we have free scaling
|
||||
|
|
@ -272,7 +270,7 @@ void FrameBufferGL::postFrameUpdate()
|
|||
glTexCoord2f(myTexCoord[0], myTexCoord[3]); glVertex2i(0, h);
|
||||
glEnd();
|
||||
|
||||
// Now show all changes made to the textures
|
||||
// Now show all changes made to the texture
|
||||
SDL_GL_SwapBuffers();
|
||||
|
||||
myDirtyFlag = false;
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: DebuggerParser.cxx,v 1.76 2005-08-20 18:19:52 urchlay Exp $
|
||||
// $Id: DebuggerParser.cxx,v 1.77 2005-09-13 18:27:42 stephena Exp $
|
||||
//============================================================================
|
||||
|
||||
#include "bspf.hxx"
|
||||
|
|
@ -1534,7 +1534,7 @@ void DebuggerParser::executeRom() {
|
|||
|
||||
// "run"
|
||||
void DebuggerParser::executeRun() {
|
||||
debugger->saveOldState(); // FIXME - why is this here?
|
||||
debugger->saveOldState();
|
||||
debugger->quit();
|
||||
commandResult = "exiting debugger";
|
||||
}
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: ContextMenu.cxx,v 1.1 2005-08-31 19:15:10 stephena Exp $
|
||||
// $Id: ContextMenu.cxx,v 1.2 2005-09-13 18:27:42 stephena Exp $
|
||||
//
|
||||
// Based on code from ScummVM - Scumm Interpreter
|
||||
// Copyright (C) 2002-2004 The ScummVM project
|
||||
|
|
@ -75,8 +75,15 @@ const string& ContextMenu::getSelectedString() const
|
|||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
void ContextMenu::handleMouseDown(int x, int y, int button, int clickCount)
|
||||
{
|
||||
// Only do a selection when the left button is in the dialog
|
||||
if(button == 1)
|
||||
sendSelection();
|
||||
{
|
||||
x += getAbsX(); y += getAbsY();
|
||||
if(x >= _x && x <= _x+_w && y >= _y && y <= _y+_h)
|
||||
sendSelection();
|
||||
else
|
||||
parent()->removeDialog();
|
||||
}
|
||||
}
|
||||
|
||||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
|
|
@ -105,6 +112,9 @@ void ContextMenu::handleKeyDown(int ascii, int keycode, int modifiers)
|
|||
{
|
||||
switch(keycode)
|
||||
{
|
||||
case 27: // escape
|
||||
parent()->removeDialog();
|
||||
break;
|
||||
case '\n': // enter/return
|
||||
case '\r':
|
||||
sendSelection();
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: RomWidget.cxx,v 1.3 2005-09-07 18:34:52 stephena Exp $
|
||||
// $Id: RomWidget.cxx,v 1.4 2005-09-13 18:27:42 stephena Exp $
|
||||
//
|
||||
// Based on code from ScummVM - Scumm Interpreter
|
||||
// Copyright (C) 2002-2004 The ScummVM project
|
||||
|
|
@ -64,7 +64,7 @@ void RomWidget::handleCommand(CommandSender* sender, int cmd, int data, int id)
|
|||
switch(cmd)
|
||||
{
|
||||
case kListScrolledCmd:
|
||||
incrementalUpdate();
|
||||
incrementalUpdate(data, myRomList->rows());
|
||||
break;
|
||||
|
||||
case kListItemChecked:
|
||||
|
|
@ -92,21 +92,25 @@ void RomWidget::handleCommand(CommandSender* sender, int cmd, int data, int id)
|
|||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
void RomWidget::loadConfig()
|
||||
{
|
||||
cerr << " ==> RomWidget::loadConfig()\n";
|
||||
|
||||
Debugger& dbg = instance()->debugger();
|
||||
|
||||
// Only reload full bank when necessary
|
||||
// if(myFirstLoad || myCurrentBank != instance()->debugger().getBank())
|
||||
// FIXME - always do a full reload for now, will optimize later
|
||||
if(true)
|
||||
if(myFirstLoad || myCurrentBank != instance()->debugger().getBank())
|
||||
{
|
||||
initialUpdate();
|
||||
myFirstLoad = false;
|
||||
}
|
||||
else // only reload what's in current view
|
||||
{
|
||||
incrementalUpdate();
|
||||
incrementalUpdate(myRomList->currentPos(), myRomList->rows());
|
||||
}
|
||||
|
||||
myCurrentBank = dbg.getBank();
|
||||
|
||||
// Update romlist to point to current PC
|
||||
int pc = instance()->debugger().cpuDebug().pc();
|
||||
int pc = dbg.cpuDebug().pc();
|
||||
AddrToLine::iterator iter = myLineList.find(pc);
|
||||
if(iter != myLineList.end())
|
||||
myRomList->setHighlighted(iter->second);
|
||||
|
|
@ -117,8 +121,6 @@ void RomWidget::initialUpdate()
|
|||
{
|
||||
Debugger& dbg = instance()->debugger();
|
||||
|
||||
myCurrentBank = dbg.getBank();
|
||||
|
||||
// Fill romlist the current bank of source or disassembly
|
||||
if(mySourceAvailable)
|
||||
; // FIXME
|
||||
|
|
@ -131,7 +133,7 @@ void RomWidget::initialUpdate()
|
|||
StringList label, data, disasm;
|
||||
BoolArray state;
|
||||
|
||||
// Disassemble entire bank (up to 4096 lines)
|
||||
// Disassemble entire bank (up to 4096 lines) and invalidate all lines
|
||||
dbg.disassemble(myAddrList, label, data, disasm, 0xf000, 4096);
|
||||
for(unsigned int i = 0; i < data.size(); ++i)
|
||||
state.push_back(false);
|
||||
|
|
@ -146,7 +148,7 @@ void RomWidget::initialUpdate()
|
|||
}
|
||||
|
||||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
void RomWidget::incrementalUpdate()
|
||||
void RomWidget::incrementalUpdate(int line, int rows)
|
||||
{
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: RomWidget.hxx,v 1.2 2005-09-07 18:34:52 stephena Exp $
|
||||
// $Id: RomWidget.hxx,v 1.3 2005-09-13 18:27:42 stephena Exp $
|
||||
//
|
||||
// Based on code from ScummVM - Scumm Interpreter
|
||||
// Copyright (C) 2002-2004 The ScummVM project
|
||||
|
|
@ -47,7 +47,7 @@ class RomWidget : public Widget, public CommandSender
|
|||
|
||||
private:
|
||||
void initialUpdate();
|
||||
void incrementalUpdate();
|
||||
void incrementalUpdate(int line, int rows);
|
||||
|
||||
void setBreak(int data);
|
||||
void setPC(int data);
|
||||
|
|
@ -63,6 +63,10 @@ class RomWidget : public Widget, public CommandSender
|
|||
/** List of line numbers indexed by address */
|
||||
AddrToLine myLineList;
|
||||
|
||||
/** Indicates whether a given line is valid or not;
|
||||
Invalid lines need to be disassembled again */
|
||||
BoolArray myLineValid;
|
||||
|
||||
bool myFirstLoad;
|
||||
bool mySourceAvailable;
|
||||
int myCurrentBank;
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: Settings.cxx,v 1.59 2005-09-11 15:44:51 stephena Exp $
|
||||
// $Id: Settings.cxx,v 1.60 2005-09-13 18:27:42 stephena Exp $
|
||||
//============================================================================
|
||||
|
||||
#include <cassert>
|
||||
|
|
@ -39,7 +39,6 @@ Settings::Settings(OSystem* osystem)
|
|||
|
||||
// Now fill it with options that are common to all versions of Stella
|
||||
set("video", "soft");
|
||||
set("video_driver", "");
|
||||
|
||||
set("gl_filter", "nearest");
|
||||
set("gl_aspect", "2.0");
|
||||
|
|
@ -47,8 +46,8 @@ Settings::Settings(OSystem* osystem)
|
|||
|
||||
set("zoom", "2");
|
||||
set("fullscreen", "false");
|
||||
set("grabmouse", "false");
|
||||
set("center", "true");
|
||||
set("grabmouse", "false");
|
||||
set("palette", "standard");
|
||||
set("debugheight", "0");
|
||||
|
||||
|
|
@ -255,7 +254,6 @@ void Settings::usage()
|
|||
<< " soft SDL software mode\n"
|
||||
#ifdef DISPLAY_OPENGL
|
||||
<< " gl SDL OpenGL mode\n"
|
||||
<< " -video_driver <type> SDL Video driver (see manual).\n"
|
||||
<< endl
|
||||
<< " -gl_filter <type> Type is one of the following:\n"
|
||||
<< " nearest Normal scaling (GL_NEAREST)\n"
|
||||
|
|
@ -266,22 +264,19 @@ void Settings::usage()
|
|||
#endif
|
||||
<< " -zoom <size> Makes window be 'size' times normal\n"
|
||||
<< " -fullscreen <1|0> Play the game in fullscreen mode\n"
|
||||
<< " -grabmouse <1|0> Keeps the mouse in the game window\n"
|
||||
<< " -center <1|0> Centers game window (if possible)\n"
|
||||
<< " -grabmouse <1|0> Keeps the mouse in the game window\n"
|
||||
<< " -palette <original| Use the specified color palette\n"
|
||||
<< " standard|\n"
|
||||
<< " z26>\n"
|
||||
<< " -framerate <number> Display the given number of frames per second\n"
|
||||
<< " -debug <1|0> Start in the debugger\n"
|
||||
<< " -debugheight <number> Set height of debugger in lines of text (NOT pixels)\n"
|
||||
<< " -holdreset Start the emulator with the Game Reset switch held down\n"
|
||||
<< " -holdselect Start the emulator with the Game Select switch held down\n"
|
||||
<< " -holdbutton0 Start the emulator with the left joystick button held down\n"
|
||||
<< endl
|
||||
#ifdef SOUND_SUPPORT
|
||||
<< " -sound <1|0> Enable sound generation\n"
|
||||
<< " -channels <1|2> Enable mono or stereo sound\n"
|
||||
<< " -fragsize <number> The size of sound fragments (must be a power of two)\n"
|
||||
<< " -volume <number> Set the volume (0 - 100)\n"
|
||||
<< endl
|
||||
#endif
|
||||
<< " -paddle <0|1|2|3> Indicates which paddle the mouse should emulate\n"
|
||||
<< " -showinfo <1|0> Shows some game info\n"
|
||||
|
|
@ -292,6 +287,7 @@ void Settings::usage()
|
|||
<< " -ssdir <path> The directory to save snapshot files to\n"
|
||||
<< " -ssname <name> How to name the snapshot (romname or md5sum)\n"
|
||||
<< " -sssingle <1|0> Generate single snapshot instead of many\n"
|
||||
<< endl
|
||||
#endif
|
||||
<< " -listrominfo Display contents of stella.pro, one line per ROM entry\n"
|
||||
<< " -help Show the text you're now reading\n"
|
||||
|
|
@ -299,6 +295,12 @@ void Settings::usage()
|
|||
<< " The following options are meant for developers\n"
|
||||
<< " Arguments are more fully explained in the manual\n"
|
||||
<< endl
|
||||
<< " -debugheight <number> Set height of debugger in lines of text (NOT pixels)\n"
|
||||
<< " -debug Start in debugger mode\n"
|
||||
<< " -holdreset Start the emulator with the Game Reset switch held down\n"
|
||||
<< " -holdselect Start the emulator with the Game Select switch held down\n"
|
||||
<< " -holdbutton0 Start the emulator with the left joystick button held down\n"
|
||||
<< endl
|
||||
<< " -pro <props file> Use the given properties file instead of stella.pro\n"
|
||||
<< " -type <arg> Sets the 'Cartridge.Type' property\n"
|
||||
<< " -ld <arg> Sets the 'Console.LeftDifficulty' property\n"
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: ListWidget.cxx,v 1.30 2005-09-07 18:34:52 stephena Exp $
|
||||
// $Id: ListWidget.cxx,v 1.31 2005-09-13 18:27:42 stephena Exp $
|
||||
//
|
||||
// Based on code from ScummVM - Scumm Interpreter
|
||||
// Copyright (C) 2002-2004 The ScummVM project
|
||||
|
|
@ -147,6 +147,7 @@ void ListWidget::scrollBarRecalc()
|
|||
_scrollBar->recalc();
|
||||
|
||||
setDirty(); draw();
|
||||
sendCommand(kListScrolledCmd, _currentPos, _id);
|
||||
}
|
||||
|
||||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
|
|
@ -366,20 +367,16 @@ void ListWidget::handleCommand(CommandSender* sender, int cmd, int data, int id)
|
|||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
void ListWidget::scrollToCurrent(int item)
|
||||
{
|
||||
bool scrolled = false;
|
||||
|
||||
// Only do something if the current item is not in our view port
|
||||
if (item < _currentPos)
|
||||
{
|
||||
// it's above our view
|
||||
_currentPos = item;
|
||||
scrolled = true;
|
||||
}
|
||||
else if (item >= _currentPos + _rows )
|
||||
{
|
||||
// it's below our view
|
||||
_currentPos = item - _rows + 1;
|
||||
scrolled = true;
|
||||
}
|
||||
|
||||
if (_currentPos < 0 || _rows > (int)_list.size())
|
||||
|
|
@ -387,12 +384,13 @@ void ListWidget::scrollToCurrent(int item)
|
|||
else if (_currentPos + _rows > (int)_list.size())
|
||||
_currentPos = _list.size() - _rows;
|
||||
|
||||
int oldScrollPos = _scrollBar->_currentPos;
|
||||
_scrollBar->_currentPos = _currentPos;
|
||||
_scrollBar->recalc();
|
||||
|
||||
setDirty(); draw();
|
||||
|
||||
if(scrolled)
|
||||
if(oldScrollPos != _currentPos)
|
||||
sendCommand(kListScrolledCmd, _currentPos, _id);
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: ListWidget.hxx,v 1.12 2005-08-26 16:44:17 stephena Exp $
|
||||
// $Id: ListWidget.hxx,v 1.13 2005-09-13 18:27:42 stephena Exp $
|
||||
//
|
||||
// Based on code from ScummVM - Scumm Interpreter
|
||||
// Copyright (C) 2002-2004 The ScummVM project
|
||||
|
|
@ -48,6 +48,9 @@ class ListWidget : public EditableWidget
|
|||
int x, int y, int w, int h);
|
||||
virtual ~ListWidget();
|
||||
|
||||
int rows() const { return _rows; }
|
||||
int currentPos() const { return _currentPos; }
|
||||
|
||||
int getSelected() const { return _selectedItem; }
|
||||
void setSelected(int item);
|
||||
|
||||
|
|
|
|||
|
|
@ -13,7 +13,7 @@
|
|||
// See the file "license" for information on usage and redistribution of
|
||||
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||||
//
|
||||
// $Id: SettingsWin32.cxx,v 1.17 2005-08-24 01:07:37 stephena Exp $
|
||||
// $Id: SettingsWin32.cxx,v 1.18 2005-09-13 18:27:42 stephena Exp $
|
||||
//============================================================================
|
||||
|
||||
#include <sstream>
|
||||
|
|
@ -28,9 +28,8 @@
|
|||
SettingsWin32::SettingsWin32(OSystem* osystem)
|
||||
: Settings(osystem)
|
||||
{
|
||||
set("video_driver", "directx"); // This seems to be much faster than DirectX
|
||||
set("fragsize", "2048"); // Anything less than this usually causes sound skipping
|
||||
set("video", "hard"); // Use software mode with hardware surface
|
||||
set("fragsize", "2048"); // Anything less than this usually causes sound skipping
|
||||
set("video", "hard"); // Use software mode with hardware surface
|
||||
}
|
||||
|
||||
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||||
|
|
|
|||
Loading…
Reference in New Issue