diff options
Diffstat (limited to 'blastem.c')
| -rw-r--r-- | blastem.c | 51 |
1 files changed, 48 insertions, 3 deletions
@@ -383,8 +383,9 @@ m68k_context * vdp_port_write_b(uint32_t vdp_port, m68k_context * context, uint8 return vdp_port_write(vdp_port, context, vdp_port < 0x10 ? value | value << 8 : ((vdp_port & 1) ? value : 0)); } -z80_context * z80_vdp_port_write(uint16_t vdp_port, z80_context * context, uint8_t value) +void * z80_vdp_port_write(uint32_t vdp_port, void * vcontext, uint8_t value) { + z80_context * context = vcontext; genesis_context * gen = context->system; if (vdp_port & 0xE0) { printf("machine freeze due to write to Z80 address %X\n", 0x7F00 | vdp_port); @@ -453,6 +454,34 @@ uint8_t vdp_port_read_b(uint32_t vdp_port, m68k_context * context) } } +uint8_t z80_vdp_port_read(uint32_t vdp_port, void * vcontext) +{ + z80_context * context = vcontext; + if (vdp_port & 0xE0) { + printf("machine freeze due to read from Z80 address %X\n", 0x7F00 | vdp_port); + exit(1); + } + genesis_context * gen = context->system; + vdp_port &= 0x1F; + uint16_t ret; + if (vdp_port < 0x10) { + //These probably won't currently interact well with the 68K accessing the VDP + vdp_run_context(gen->vdp, context->current_cycle * MCLKS_PER_Z80); + if (vdp_port < 4) { + ret = vdp_data_port_read(gen->vdp); + } else if (vdp_port < 8) { + ret = vdp_control_port_read(gen->vdp); + } else { + printf("Illegal write to HV Counter port %X\n", vdp_port); + exit(1); + } + } else { + //TODO: Figure out the correct value today + ret = 0xFFFF; + } + return vdp_port & 1 ? ret : ret >> 8; +} + uint32_t zram_counter = 0; #define Z80_ACK_DELAY 3 #define Z80_BUSY_DELAY 1//TODO: Find the actual value for this @@ -674,8 +703,9 @@ uint16_t io_read_w(uint32_t location, m68k_context * context) return value; } -z80_context * z80_write_ym(uint16_t location, z80_context * context, uint8_t value) +void * z80_write_ym(uint32_t location, void * vcontext, uint8_t value) { + z80_context * context = vcontext; genesis_context * gen = context->system; sync_sound(gen, context->current_cycle * MCLKS_PER_Z80); if (location & 1) { @@ -688,13 +718,28 @@ z80_context * z80_write_ym(uint16_t location, z80_context * context, uint8_t val return context; } -uint8_t z80_read_ym(uint16_t location, z80_context * context) +uint8_t z80_read_ym(uint32_t location, void * vcontext) { + z80_context * context = vcontext; genesis_context * gen = context->system; sync_sound(gen, context->current_cycle * MCLKS_PER_Z80); return ym_read_status(gen->ym); } +uint8_t z80_read_bank(uint32_t location, void * vcontext) +{ + z80_context * context = vcontext; + //TODO: Implement me + return 0; +} + +void *z80_write_bank(uint32_t location, void * vcontext, uint8_t value) +{ + z80_context * context = vcontext; + //TODO: Implement me + return context; +} + uint16_t read_sram_w(uint32_t address, m68k_context * context) { genesis_context * gen = context->system; |