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bsnes/processor/hg51b/hg51b.cpp

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Update to v087r08 release. byuu says: Added some more ARM opcodes, hooked up MMIO. Bind it with mmio[(addr 000-3ff)] = this; inside CPU/PPU/APU, goes to read(), write(). Also moved the Hitachi HG51B core to processor/, and split it apart from the snes/chip/hitachidsp implementation. This one actually worked really well. Very clean split between MMIO/DMA and the processor core. I may move a more generic DMA function inside the core, not sure yet. I still believe the HG51B169 to be a variant of the HG51BS family, but given they're meant to be incredibly flexible microcontrollers, it's possible that each variant gets its own instruction set. So, who knows. We'll worry about it if we ever find another HG51B DSP, I guess. GBA BIOS is constantly reading from 04000300, but it never writes. If I return prng()&1, I can get it to proceed until it hits a bad opcode (stc opcode, which the GBA lacks a coprocessor so ... bad codepath.) Without it, it just reads that register forever and keeps resetting the system, or something ... I guess we're going to have to try and get ARMwrestler working, because the BIOS seems to need too much emulation code to do anything at all.
2012-03-24 07:52:36 +00:00
#include <processor/processor.hpp>
#include "hg51b.hpp"
namespace Processor {
#include "registers.cpp"
#include "instructions.cpp"
#include "serialization.cpp"
void HG51B::exec(uint24 addr) {
if(regs.halt) return;
addr = addr + regs.pc * 2;
opcode = bus_read(addr++) << 0;
opcode |= bus_read(addr++) << 8;
regs.pc = (regs.pc & 0xffff00) | ((regs.pc + 1) & 0x0000ff);
instruction();
}
void HG51B::power() {
regs.halt = true;
regs.n = 0;
regs.z = 0;
regs.c = 0;
}
}