diff options
| author | Mike Pavone <pavone@retrodev.com> | 2013-09-18 19:10:54 -0700 |
|---|---|---|
| committer | Mike Pavone <pavone@retrodev.com> | 2013-09-18 19:10:54 -0700 |
| commit | 5830e5828c4680aafe27210935dd3fed9ece0448 (patch) | |
| tree | 32c4ca3e1e625b29babb8585165110ab9250282e /blastem.c | |
| parent | b5767c17b138cfb9b264dbc9cad38252cdd2731c (diff) | |
Theoretically more correct timing of Z80 bus request
Diffstat (limited to 'blastem.c')
| -rw-r--r-- | blastem.c | 5 |
1 files changed, 3 insertions, 2 deletions
@@ -517,7 +517,6 @@ m68k_context * io_write(uint32_t location, m68k_context * context, uint8_t value } } else { if (location == 0x1100) { - sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K); if (busack_cycle <= context->current_cycle) { busack = new_busack; busack_cycle = CYCLE_NEVER; @@ -526,11 +525,13 @@ m68k_context * io_write(uint32_t location, m68k_context * context, uint8_t value dputs("bus requesting Z80"); if(!reset && !busreq) { - busack_cycle = ((gen->z80->current_cycle + Z80_ACK_DELAY) * MCLKS_PER_Z80) / MCLKS_PER_68K;//context->current_cycle + Z80_ACK_DELAY; + sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K + Z80_ACK_DELAY*MCLKS_PER_Z80); + busack_cycle = (gen->z80->current_cycle * MCLKS_PER_Z80) / MCLKS_PER_68K;//context->current_cycle + Z80_ACK_DELAY; new_busack = Z80_REQ_ACK; } busreq = 1; } else { + sync_z80(gen->z80, context->current_cycle * MCLKS_PER_68K); if (busreq) { dputs("releasing z80 bus"); #ifdef DO_DEBUG_PRINT |