Mercurial > repos > blastem
changeset 137:0e7e1ccc0a81
Implemented HV counter
| author | Mike Pavone <pavone@retrodev.com> |
|---|---|
| date | Sun, 30 Dec 2012 22:39:41 -0800 |
| parents | e64554246d11 |
| children | aa3e1bb338c9 |
| files | blastem.c runtime.S vdp.c vdp.h |
| diffstat | 4 files changed, 57 insertions(+), 2 deletions(-) [+] |
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--- a/blastem.c Sun Dec 30 18:40:33 2012 -0800 +++ b/blastem.c Sun Dec 30 22:39:41 2012 -0800 @@ -167,8 +167,8 @@ } else if(vdp_port < 8) { context->value = vdp_control_port_read(v_context); } else { - //TODO: Implement H/V counter - context->value = 0; + context->value = vdp_hv_counter_read(v_context); + //printf("HV Counter: %X at cycle %d\n", context->value, v_context->cycles); } context->current_cycle = v_context->cycles/MCLKS_PER_68K; } else {
--- a/runtime.S Sun Dec 30 18:40:33 2012 -0800 +++ b/runtime.S Sun Dec 30 22:39:41 2012 -0800 @@ -369,6 +369,8 @@ jbe cart_b cmp $0xE00000, %ecx jae workram_b + cmp $0xC00000, %ecx + jae vdp_psg_b cmp $0xA10000, %ecx jb not_io_b cmp $0xA12000, %ecx @@ -378,6 +380,17 @@ xor %cl, %cl dec %cl ret +vdp_psg_b: + test $0x2700E0, %ecx + jnz crash + and $0x1F, %ecx + bt $0, %ecx + jnc vdp_swap + jmp do_vdp_port_read +vdp_swap: + call do_vdp_port_read + shr $8, %cx + ret workram_b: /* deal with byte swapping */ xor $1, %ecx
--- a/vdp.c Sun Dec 30 18:40:33 2012 -0800 +++ b/vdp.c Sun Dec 30 22:39:41 2012 -0800 @@ -1092,6 +1092,10 @@ if (context->flags & FLAG_DMA_RUN) { value |= 0x20; } + uint32_t line= context->cycles / MCLKS_LINE; + if (line >= (context->latched_mode & BIT_PAL ? PAL_ACTIVE : NTSC_ACTIVE)) { + value |= 0x8; + } //TODO: Lots of other bits in status port return value; } @@ -1131,6 +1135,43 @@ return value; } +uint16_t vdp_hv_counter_read(vdp_context * context) +{ + uint32_t line= context->cycles / MCLKS_LINE; + if (!line) { + line = 0xFF; + } else { + line--; + if (line > 0xEA) { + line = (line + 0xFA) & 0xFF; + } + } + uint32_t linecyc = context->cycles % MCLKS_LINE; + if (context->latched_mode & BIT_H40) { + linecyc /= 8; + if (linecyc >= 86) { + linecyc -= 86; + } else { + linecyc += 334; + } + if (linecyc > 0x16C) { + linecyc += 92; + } + } else { + linecyc /= 10; + if (linecyc >= 74) { + linecyc -= 74; + } else { + linecyc += 268; + } + if (linecyc > 0x127) { + linecyc += 170; + } + } + linecyc &= 0xFF; + return (line << 8) | linecyc; +} + void vdp_adjust_cycles(vdp_context * context, uint32_t deduction) { context->cycles -= deduction;
--- a/vdp.h Sun Dec 30 18:40:33 2012 -0800 +++ b/vdp.h Sun Dec 30 22:39:41 2012 -0800 @@ -127,6 +127,7 @@ void vdp_data_port_write(vdp_context * context, uint16_t value); uint16_t vdp_control_port_read(vdp_context * context); uint16_t vdp_data_port_read(vdp_context * context); +uint16_t vdp_hv_counter_read(vdp_context * context); void vdp_adjust_cycles(vdp_context * context, uint32_t deduction); #endif //VDP_H_