diff options
| author | Michael Pavone <pavone@retrodev.com> | 2014-12-26 19:37:59 -0800 |
|---|---|---|
| committer | Michael Pavone <pavone@retrodev.com> | 2014-12-26 19:37:59 -0800 |
| commit | 21cbee7575fce46e9730bef9df4d1e7eea819793 (patch) | |
| tree | 0e8f462a868857cdd03d04dab93a0f4dcff33af5 /blastem.c | |
| parent | 4302e0d4fde15ebc79bc2e0f0cc2cf1246ba1074 (diff) | |
Get Z80 banked access sort of working again
Diffstat (limited to 'blastem.c')
| -rw-r--r-- | blastem.c | 35 |
1 files changed, 28 insertions, 7 deletions
@@ -731,14 +731,35 @@ uint8_t z80_read_ym(uint32_t location, void * vcontext) uint8_t z80_read_bank(uint32_t location, void * vcontext) { z80_context * context = vcontext; - //TODO: Implement me + uint32_t address = context->bank_reg << 15 | location; + fprintf(stderr, "Unhandled read by Z80 from address %X through banked memory area\n", address); return 0; } void *z80_write_bank(uint32_t location, void * vcontext, uint8_t value) { z80_context * context = vcontext; - //TODO: Implement me + uint32_t address = context->bank_reg << 15 | location; + if (address >= 0xE00000) { + address &= 0xFFFF; + ((uint8_t *)ram)[address ^ 1] = value; + } else { + fprintf(stderr, "Unhandled write by Z80 to address %X through banked memory area\n", address); + } + return context; +} + +void *z80_write_bank_reg(uint32_t location, void * vcontext, uint8_t value) +{ + z80_context * context = vcontext; + + context->bank_reg = (context->bank_reg >> 1 | value << 8) & 0x1FF; + if (context->bank_reg < 0x80) { + context->mem_pointers[1] = context->mem_pointers[2] + (context->bank_reg << 15); + } else { + context->mem_pointers[1] = NULL; + } + return context; } @@ -1121,11 +1142,11 @@ void detect_region() } #ifndef NO_Z80 const memmap_chunk z80_map[] = { - { 0x0000, 0x4000, 0x1FFF, 0, MMAP_READ | MMAP_WRITE | MMAP_CODE, z80_ram, NULL, NULL, NULL, NULL }, - { 0x8000, 0x10000, 0xFFFF, 1, MMAP_READ | MMAP_WRITE | MMAP_PTR_IDX | MMAP_FUNC_NULL, NULL, NULL, NULL, z80_read_bank, z80_write_bank}, - { 0x4000, 0x6000, 0x0003, 0, MMAP_READ | MMAP_WRITE, NULL, NULL, NULL, z80_read_ym, z80_write_ym}, - { 0x6000, 0x6100, 0xFFFF, 0, MMAP_WRITE | MMAP_CUSTOM, NULL, NULL, NULL, NULL, (write_8_fun)z80_gen_bank_write}, - { 0x7F00, 0x8000, 0x00FF, 0, MMAP_READ | MMAP_WRITE, NULL, NULL, NULL, z80_vdp_port_read, z80_vdp_port_write} + { 0x0000, 0x4000, 0x1FFF, 0, MMAP_READ | MMAP_WRITE | MMAP_CODE, z80_ram, NULL, NULL, NULL, NULL }, + { 0x8000, 0x10000, 0xFFFF, 1, MMAP_READ | MMAP_PTR_IDX | MMAP_FUNC_NULL | MMAP_BYTESWAP, NULL, NULL, NULL, z80_read_bank, z80_write_bank}, + { 0x4000, 0x6000, 0x0003, 0, 0, NULL, NULL, NULL, z80_read_ym, z80_write_ym}, + { 0x6000, 0x6100, 0xFFFF, 0, 0, NULL, NULL, NULL, NULL, z80_write_bank_reg}, + { 0x7F00, 0x8000, 0x00FF, 0, 0, NULL, NULL, NULL, z80_vdp_port_read, z80_vdp_port_write} }; #endif |