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Initial implementation of channel 3 special mode
author Mike Pavone <pavone@retrodev.com>
date Tue, 04 Jun 2013 21:23:12 -0700
parents b904859964e5
children 6e5c4f3ab0e2
comparison
equal deleted inserted replaced
382:b904859964e5 383:72933100c55c
452 { 452 {
453 uint32_t chan_num = op / 4; 453 uint32_t chan_num = op / 4;
454 //printf("ym_update_phase_inc | channel: %d, op: %d\n", chan_num, op); 454 //printf("ym_update_phase_inc | channel: %d, op: %d\n", chan_num, op);
455 //base frequency 455 //base frequency
456 ym_channel * channel = context->channels + chan_num; 456 ym_channel * channel = context->channels + chan_num;
457 uint32_t inc = channel->fnum; 457 uint32_t inc, detune;
458 if (!channel->block) { 458 if (chan_num == 2 && context->ch3_mode && (op < (2*4 + 3))) {
459 inc >>= 1; 459 inc = context->ch3_supp[op-2*4].fnum;
460 if (!context->ch3_supp[op-2*4].block) {
461 inc >>= 1;
462 } else {
463 inc <<= (context->ch3_supp[op-2*4].block-1);
464 }
465 //detune
466 detune = detune_table[context->ch3_supp[op-2*4].keycode][operator->detune & 0x3];
460 } else { 467 } else {
461 inc <<= (channel->block-1); 468 inc = channel->fnum;
462 } 469 if (!channel->block) {
463 //detune 470 inc >>= 1;
464 uint32_t detune = detune_table[channel->keycode][operator->detune & 0x3]; 471 } else {
472 inc <<= (channel->block-1);
473 }
474 //detune
475 detune = detune_table[channel->keycode][operator->detune & 0x3];
476 }
465 if (operator->detune & 0x40) { 477 if (operator->detune & 0x40) {
466 inc -= detune; 478 inc -= detune;
467 //this can underflow, mask to 17-bit result 479 //this can underflow, mask to 17-bit result
468 inc &= 0x1FFFF; 480 inc &= 0x1FFFF;
469 } else { 481 } else {
500 context->timer_a_load |= value & 0x3; 512 context->timer_a_load |= value & 0x3;
501 break; 513 break;
502 case REG_TIMERB: 514 case REG_TIMERB:
503 context->timer_b_load = value; 515 context->timer_b_load = value;
504 break; 516 break;
505 case REG_TIME_CTRL: 517 case REG_TIME_CTRL: {
506 context->timer_control = value; 518 context->timer_control = value & 0x3F;
519 uint8_t old_mode = context->ch3_mode;
520 context->ch3_mode = value & 0xC0;
521 if (context->ch3_mode != old_mode) {
522 ym_update_phase_inc(context, context->operators + 2*4, 2*4);
523 ym_update_phase_inc(context, context->operators + 2*4+1, 2*4+1);
524 ym_update_phase_inc(context, context->operators + 2*4+2, 2*4+2);
525 }
507 break; 526 break;
527 }
508 case REG_KEY_ONOFF: { 528 case REG_KEY_ONOFF: {
509 uint8_t channel = value & 0x7; 529 uint8_t channel = value & 0x7;
510 if (channel < NUM_CHANNELS) { 530 if (channel < NUM_CHANNELS) {
511 for (uint8_t op = channel * 4, bit = 0x10; op < (channel + 1) * 4; op++, bit <<= 1) { 531 for (uint8_t op = channel * 4, bit = 0x10; op < (channel + 1) * 4; op++, bit <<= 1) {
512 if (value & bit) { 532 if (value & bit) {
589 break; 609 break;
590 case REG_BLOCK_FNUM_H:{ 610 case REG_BLOCK_FNUM_H:{
591 context->channels[channel].block_fnum_latch = value; 611 context->channels[channel].block_fnum_latch = value;
592 break; 612 break;
593 } 613 }
594 //TODO: Channel 3 special/CSM modes 614 case REG_FNUM_LOW_CH3:
615 if (channel < 3) {
616 context->ch3_supp[channel].block = context->ch3_supp[channel].block_fnum_latch >> 3 & 0x7;
617 context->ch3_supp[channel].fnum = (context->ch3_supp[channel].block_fnum_latch & 0x7) << 8 | value;
618 context->ch3_supp[channel].keycode = context->ch3_supp[channel].block << 2 | fnum_to_keycode[context->ch3_supp[channel].fnum >> 7];
619 if (context->ch3_mode) {
620 ym_update_phase_inc(context, context->operators + 2*4 + channel, 2*4);
621 }
622 }
623 break;
624 case REG_BLOCK_FN_CH3:
625 if (channel < 3) {
626 context->ch3_supp[channel].block_fnum_latch = value;
627 }
628 break;
595 case REG_ALG_FEEDBACK: 629 case REG_ALG_FEEDBACK:
596 context->channels[channel].algorithm = value & 0x7; 630 context->channels[channel].algorithm = value & 0x7;
597 context->channels[channel].feedback = value >> 3 & 0x7; 631 context->channels[channel].feedback = value >> 3 & 0x7;
598 break; 632 break;
599 case REG_LR_AMS_PMS: 633 case REG_LR_AMS_PMS: