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-rw-r--r--ym2612.c157
1 files changed, 107 insertions, 50 deletions
diff --git a/ym2612.c b/ym2612.c
index de707c7..10cb0a0 100644
--- a/ym2612.c
+++ b/ym2612.c
@@ -466,59 +466,19 @@ void ym_run(ym2612_context * context, uint32_t to_cycle)
uint16_t phase = operator->phase_counter >> 10 & 0x3FF;
operator->phase_counter += ym_calc_phase_inc(context, operator, context->current_op);
int16_t mod = 0;
- switch (op % 4)
- {
- case 0://Operator 1
+ if (op & 3) {
+ if (operator->mod_src[0]) {
+ mod = *operator->mod_src[0];
+ if (operator->mod_src[1]) {
+ mod += *
+ operator->mod_src[1];
+ }
+ mod >>= YM_MOD_SHIFT;
+ }
+ } else {
if (chan->feedback) {
mod = (chan->op1_old + operator->output) >> (10-chan->feedback);
}
- break;
- case 1://Operator 3
- switch(chan->algorithm)
- {
- case 0:
- case 2:
- //modulate by operator 2
- mod = context->operators[op+1].output >> YM_MOD_SHIFT;
- break;
- case 1:
- //modulate by operator 1+2
- mod = (context->operators[op-1].output + context->operators[op+1].output) >> YM_MOD_SHIFT;
- break;
- case 5:
- //modulate by operator 1
- mod = context->operators[op-1].output >> YM_MOD_SHIFT;
- }
- break;
- case 2://Operator 2
- if (chan->algorithm != 1 && chan->algorithm != 2 && chan->algorithm != 7) {
- //modulate by Operator 1
- mod = context->operators[op-2].output >> YM_MOD_SHIFT;
- }
- break;
- case 3://Operator 4
- switch(chan->algorithm)
- {
- case 0:
- case 1:
- case 4:
- //modulate by operator 3
- mod = context->operators[op-2].output >> YM_MOD_SHIFT;
- break;
- case 2:
- //modulate by operator 1+3
- mod = (context->operators[op-3].output + context->operators[op-2].output) >> YM_MOD_SHIFT;
- break;
- case 3:
- //modulate by operator 2+3
- mod = (context->operators[op-1].output + context->operators[op-2].output) >> YM_MOD_SHIFT;
- break;
- case 5:
- //modulate by operator 1
- mod = context->operators[op-3].output >> YM_MOD_SHIFT;
- break;
- }
- break;
}
uint16_t env = operator->envelope;
if (operator->ssg) {
@@ -936,6 +896,103 @@ void ym_data_write(ym2612_context * context, uint8_t value)
break;
case REG_ALG_FEEDBACK:
context->channels[channel].algorithm = value & 0x7;
+ switch (context->channels[channel].algorithm)
+ {
+ case 0:
+ //operator 3 modulated by operator 2
+ context->operators[channel*4+1].mod_src[0] = &context->operators[channel*4+2].output;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ //operator 2 modulated by operator 1
+ context->operators[channel*4+2].mod_src[0] = &context->operators[channel*4+0].output;
+
+ //operator 4 modulated by operator 3
+ context->operators[channel*4+3].mod_src[0] = &context->operators[channel*4+1].output;
+ context->operators[channel*4+3].mod_src[1] = NULL;
+ break;
+ case 1:
+ //operator 3 modulated by operator 1+2
+ context->operators[channel*4+1].mod_src[0] = &context->operators[channel*4+0].output;
+ context->operators[channel*4+1].mod_src[1] = &context->operators[channel*4+2].output;
+
+ //operator 2 unmodulated
+ context->operators[channel*4+2].mod_src[0] = NULL;
+
+ //operator 4 modulated by operator 3
+ context->operators[channel*4+3].mod_src[0] = &context->operators[channel*4+1].output;
+ context->operators[channel*4+3].mod_src[1] = NULL;
+ break;
+ case 2:
+ //operator 3 modulated by operator 2
+ context->operators[channel*4+1].mod_src[0] = &context->operators[channel*4+2].output;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ //operator 2 unmodulated
+ context->operators[channel*4+2].mod_src[0] = NULL;
+
+ //operator 4 modulated by operator 1+3
+ context->operators[channel*4+3].mod_src[0] = &context->operators[channel*4+0].output;
+ context->operators[channel*4+3].mod_src[1] = &context->operators[channel*4+1].output;
+ break;
+ case 3:
+ //operator 3 unmodulated
+ context->operators[channel*4+1].mod_src[0] = NULL;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ //operator 2 modulated by operator 1
+ context->operators[channel*4+2].mod_src[0] = &context->operators[channel*4+0].output;
+
+ //operator 4 modulated by operator 2+3
+ context->operators[channel*4+3].mod_src[0] = &context->operators[channel*4+2].output;
+ context->operators[channel*4+3].mod_src[1] = &context->operators[channel*4+1].output;
+ break;
+ case 4:
+ //operator 3 unmodulated
+ context->operators[channel*4+1].mod_src[0] = NULL;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ //operator 2 modulated by operator 1
+ context->operators[channel*4+2].mod_src[0] = &context->operators[channel*4+0].output;
+
+ //operator 4 modulated by operator 3
+ context->operators[channel*4+3].mod_src[0] = &context->operators[channel*4+1].output;
+ context->operators[channel*4+3].mod_src[1] = NULL;
+ break;
+ case 5:
+ //operator 3 modulated by operator 1
+ context->operators[channel*4+1].mod_src[0] = &context->operators[channel*4+0].output;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ //operator 2 modulated by operator 1
+ context->operators[channel*4+2].mod_src[0] = &context->operators[channel*4+0].output;
+
+ //operator 4 modulated by operator 1
+ context->operators[channel*4+3].mod_src[0] = &context->operators[channel*4+0].output;
+ context->operators[channel*4+3].mod_src[1] = NULL;
+ break;
+ case 6:
+ //operator 3 unmodulated
+ context->operators[channel*4+1].mod_src[0] = NULL;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ //operator 2 modulated by operator 1
+ context->operators[channel*4+2].mod_src[0] = &context->operators[channel*4+0].output;
+
+ //operator 4 unmodulated
+ context->operators[channel*4+3].mod_src[0] = NULL;
+ context->operators[channel*4+3].mod_src[1] = NULL;
+ break;
+ case 7:
+ //everything is an output so no modulation (except for op 1 feedback)
+ context->operators[channel*4+1].mod_src[0] = NULL;
+ context->operators[channel*4+1].mod_src[1] = NULL;
+
+ context->operators[channel*4+2].mod_src[0] = NULL;
+
+ context->operators[channel*4+3].mod_src[0] = NULL;
+ context->operators[channel*4+3].mod_src[1] = NULL;
+ break;
+ }
context->channels[channel].feedback = value >> 3 & 0x7;
//printf("Algorithm %d, feedback %d for channel %d\n", value & 0x7, value >> 3 & 0x7, channel);
break;
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-19 19:55:27 +0000