diff options
Diffstat (limited to 'vdp.c')
| -rw-r--r-- | vdp.c | 10 |
1 files changed, 6 insertions, 4 deletions
@@ -1467,10 +1467,10 @@ int vdp_control_port_write(vdp_context * context, uint16_t value) uint8_t reg = (value >> 8) & 0x1F; if (reg < (context->regs[REG_MODE_2] & BIT_MODE_5 ? VDP_REGS : 0xA)) { //printf("register %d set to %X\n", reg, value & 0xFF); - context->regs[reg] = value; - if (reg == REG_MODE_2) { - //printf("Display is now %s\n", (context->regs[REG_MODE_2] & DISPLAY_ENABLE) ? "enabled" : "disabled"); + if (reg == REG_MODE_1 && (value & BIT_HVC_LATCH) && !(context->regs[reg] & BIT_HVC_LATCH)) { + context->hv_latch = vdp_hv_counter_read(context); } + context->regs[reg] = value; if (reg == REG_MODE_4) { context->double_res = (value & (BIT_INTERLACE | BIT_DOUBLE_RES)) == (BIT_INTERLACE | BIT_DOUBLE_RES); if (!context->double_res) { @@ -1613,7 +1613,9 @@ uint16_t vdp_data_port_read(vdp_context * context) uint16_t vdp_hv_counter_read(vdp_context * context) { - //TODO: deal with clock adjustemnts handled in vdp_run_context + if (context->regs[REG_MODE_1] & BIT_HVC_LATCH) { + return context->hv_latch; + } uint32_t line= context->cycles / MCLKS_LINE; if (!line) { line = 0xFF; |