#ifdef ARMDSP_CPP //note: timings are completely unverified //due to the ST018 chip design (on-die ROM), testing is nearly impossible void ArmDSP::bus_idle() { step(1); } uint32 ArmDSP::bus_read(unsigned mode, uint32 addr) { step(1); static auto memory = [&](const uint8 *memory, unsigned mode, uint32 addr) -> uint32 { if(mode & Word) { memory += addr & ~3; return memory[0] << 0 | memory[1] << 8 | memory[2] << 16 | memory[3] << 24; } else if(mode & Byte) { return memory[addr]; } else { return 0; //should never occur } }; switch(addr & 0xe0000000) { case 0x00000000: return memory(programROM, mode, addr & 0x1ffff); case 0x20000000: return pipeline.fetch.instruction; case 0x40000000: break; case 0x60000000: return 0x40404001; case 0x80000000: return pipeline.fetch.instruction; case 0xa0000000: return memory(dataROM, mode, addr & 0x7fff); case 0xc0000000: return pipeline.fetch.instruction; case 0xe0000000: return memory(programRAM, mode, addr & 0x3fff); } addr &= 0xe000003f; if(addr == 0x40000010) { if(bridge.cputoarm.ready) { bridge.cputoarm.ready = false; return bridge.cputoarm.data; } } if(addr == 0x40000020) { return bridge.status(); } return 0; } void ArmDSP::bus_write(unsigned mode, uint32 addr, uint32 word) { step(1); static auto memory = [](uint8 *memory, unsigned mode, uint32 addr, uint32 word) { if(mode & Word) { memory += addr & ~3; *memory++ = word >> 0; *memory++ = word >> 8; *memory++ = word >> 16; *memory++ = word >> 24; } else if(mode & Byte) { memory += addr; *memory++ = word >> 0; } }; switch(addr & 0xe0000000) { case 0x00000000: return; case 0x20000000: return; case 0x40000000: break; case 0x60000000: return; case 0x80000000: return; case 0xa0000000: return; case 0xc0000000: return; case 0xe0000000: return memory(programRAM, mode, addr & 0x3fff, word); } addr &= 0xe000003f; word &= 0x000000ff; if(addr == 0x40000000) { bridge.armtocpu.ready = true; bridge.armtocpu.data = word; return; } if(addr == 0x40000010) { bridge.signal = true; return; } if(addr == 0x40000020) { bridge.timerlatch = (bridge.timerlatch & 0xffff00) | (word << 0); return; } if(addr == 0x40000024) { bridge.timerlatch = (bridge.timerlatch & 0xff00ff) | (word << 8); return; } if(addr == 0x40000028) { bridge.timerlatch = (bridge.timerlatch & 0x00ffff) | (word << 16); return; } if(addr == 0x4000002c) { bridge.timer = bridge.timerlatch; return; } } #endif