Mercurial > repos > blastem
diff blastem.c @ 288:a8ee7934a1f8
Add a YM2612 stub implementation with just timers and status registers so that games that depend on it can run.
author | Mike Pavone <pavone@retrodev.com> |
---|---|
date | Sun, 05 May 2013 22:56:42 -0700 |
parents | 9ee64039ddeb |
children | 1cc0850ab6bc |
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--- a/blastem.c Sun May 05 11:17:37 2013 -0700 +++ b/blastem.c Sun May 05 22:56:42 2013 -0700 @@ -165,11 +165,14 @@ m68k_context * sync_components(m68k_context * context, uint32_t address) { //TODO: Handle sync targets smaller than a single frame - vdp_context * v_context = context->video_context; - z80_context * z_context = context->next_cpu; + genesis_context * gen = context->system; + vdp_context * v_context = gen->vdp; + z80_context * z_context = gen->z80; uint32_t mclks = context->current_cycle * MCLKS_PER_68K; sync_z80(z_context, mclks); if (mclks >= MCLKS_PER_FRAME) { + ym_run(gen->ym, context->current_cycle); + gen->ym->current_cycle -= MCLKS_PER_FRAME/MCLKS_PER_68K; //printf("reached frame end | 68K Cycles: %d, MCLK Cycles: %d\n", context->current_cycle, mclks); vdp_run_context(v_context, MCLKS_PER_FRAME); if (!headless) { @@ -354,6 +357,7 @@ m68k_context * io_write(uint32_t location, m68k_context * context, uint8_t value) { + genesis_context * gen = context->system; if (location < 0x10000) { if (busack_cycle > context->current_cycle) { busack = new_busack; @@ -363,7 +367,16 @@ location &= 0x7FFF; if (location < 0x4000) { z80_ram[location & 0x1FFF] = value; - z80_handle_code_write(location & 0x1FFF, context->next_cpu); + z80_handle_code_write(location & 0x1FFF, gen->z80); + } else if (location < 0x6000) { + ym_run(gen->ym, context->current_cycle); + if (location & 1) { + ym_data_write(gen->ym, value); + } else if(location & 2) { + ym_address_write_part2(gen->ym, value); + } else { + ym_address_write_part1(gen->ym, value); + } } } } else { @@ -388,7 +401,7 @@ } } else { if (location == 0x1100) { - sync_z80(context->next_cpu, context->current_cycle * MCLKS_PER_68K); + sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K); if (busack_cycle > context->current_cycle) { busack = new_busack; busack_cycle = CYCLE_NEVER; @@ -410,16 +423,15 @@ fwrite(z80_ram, 1, sizeof(z80_ram), f); fclose(f); #endif - z80_context * z_context = context->next_cpu; //TODO: Add necessary delay between release of busreq and resumption of execution - z_context->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; + gen->z80->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; } busreq = 0; busack_cycle = CYCLE_NEVER; busack = 1; } } else if (location == 0x1200) { - sync_z80(context->next_cpu, context->current_cycle * MCLKS_PER_68K); + sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K); if (value & 1) { if (reset && busreq) { new_busack = 0; @@ -427,10 +439,9 @@ } //TODO: Deal with the scenario in which reset is not asserted long enough if (reset) { - z80_context * z_context = context->next_cpu; need_reset = 1; //TODO: Add necessary delay between release of reset and start of execution - z_context->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; + gen->z80->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; } reset = 0; } else { @@ -444,6 +455,7 @@ m68k_context * io_write_w(uint32_t location, m68k_context * context, uint16_t value) { + genesis_context * gen = context->system; if (location < 0x10000) { if (busack_cycle > context->current_cycle) { busack = new_busack; @@ -453,7 +465,16 @@ location &= 0x7FFF; if (location < 0x4000) { z80_ram[location & 0x1FFE] = value >> 8; - z80_handle_code_write(location & 0x1FFE, context->next_cpu); + z80_handle_code_write(location & 0x1FFE, gen->z80); + } else if (location < 0x6000) { + ym_run(gen->ym, context->current_cycle); + if (location & 1) { + ym_data_write(gen->ym, value >> 8); + } else if(location & 2) { + ym_address_write_part2(gen->ym, value >> 8); + } else { + ym_address_write_part1(gen->ym, value >> 8); + } } } } else { @@ -479,7 +500,7 @@ } else { //printf("IO Write of %X to %X @ %d\n", value, location, context->current_cycle); if (location == 0x1100) { - sync_z80(context->next_cpu, context->current_cycle * MCLKS_PER_68K); + sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K); if (busack_cycle > context->current_cycle) { busack = new_busack; busack_cycle = CYCLE_NEVER; @@ -501,16 +522,15 @@ fwrite(z80_ram, 1, sizeof(z80_ram), f); fclose(f); #endif - z80_context * z_context = context->next_cpu; //TODO: Add necessary delay between release of busreq and resumption of execution - z_context->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; + gen->z80->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; } busreq = 0; busack_cycle = CYCLE_NEVER; busack = 1; } } else if (location == 0x1200) { - sync_z80(context->next_cpu, context->current_cycle * MCLKS_PER_68K); + sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K); if (value & 0x100) { if (reset && busreq) { new_busack = 0; @@ -518,10 +538,9 @@ } //TODO: Deal with the scenario in which reset is not asserted long enough if (reset) { - z80_context * z_context = context->next_cpu; need_reset = 1; //TODO: Add necessary delay between release of reset and start of execution - z_context->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; + gen->z80->current_cycle = (context->current_cycle * MCLKS_PER_68K) / MCLKS_PER_Z80; } reset = 0; } else { @@ -541,6 +560,7 @@ m68k_context * io_read(uint32_t location, m68k_context * context) { + genesis_context *gen = context->system; if (location < 0x10000) { if (busack_cycle > context->current_cycle) { busack = new_busack; @@ -550,6 +570,9 @@ location &= 0x7FFF; if (location < 0x4000) { context->value = z80_ram[location & 0x1FFF]; + } else if (location < 0x6000) { + ym_run(gen->ym, context->current_cycle); + context->value = ym_read_status(gen->ym); } else { context->value = 0xFF; } @@ -601,6 +624,7 @@ m68k_context * io_read_w(uint32_t location, m68k_context * context) { + genesis_context * gen = context->system; if (location < 0x10000) { if (busack_cycle > context->current_cycle) { busack = new_busack; @@ -608,12 +632,16 @@ } if (!(busack || reset)) { location &= 0x7FFF; + uint16_t value; if (location < 0x4000) { - context->value = z80_ram[location & 0x1FFE]; - context->value |= context->value << 8; + value = z80_ram[location & 0x1FFE]; + } else if (location < 0x6000) { + ym_run(gen->ym, context->current_cycle); + value = ym_read_status(gen->ym); } else { - context->value = 0xFFFF; + value = 0xFF; } + context->value = value | (value << 8); } else { context->value = 0xFFFF; } @@ -894,16 +922,17 @@ return context; } -void init_run_cpu(vdp_context * vcontext, z80_context * zcontext, int debug, FILE * address_log) +void init_run_cpu(genesis_context * gen, int debug, FILE * address_log) { m68k_context context; x86_68k_options opts; + gen->m68k = &context; init_x86_68k_opts(&opts); opts.address_log = address_log; init_68k_context(&context, opts.native_code_map, &opts); - context.video_context = vcontext; - context.next_cpu = zcontext; + context.video_context = gen->vdp; + context.system = gen; //cartridge ROM context.mem_pointers[0] = cart; context.target_cycle = context.sync_cycle = MCLKS_PER_FRAME/MCLKS_PER_68K; @@ -972,6 +1001,9 @@ init_vdp_context(&v_context); + ym2612_context y_context; + ym_init(&y_context); + z80_context z_context; x86_z80_options z_opts; init_x86_z80_opts(&z_opts); @@ -982,6 +1014,11 @@ z_context.int_cycle = CYCLE_NEVER; z_context.mem_pointers[1] = z_context.mem_pointers[2] = (uint8_t *)cart; - init_run_cpu(&v_context, &z_context, debug, address_log); + genesis_context gen; + gen.z80 = &z_context; + gen.vdp = &v_context; + gen.ym = &y_context; + + init_run_cpu(&gen, debug, address_log); return 0; }