Mercurial > repos > blastem
view rf5c164.c @ 2329:06d5e9b08bdb
Add NTSC composite shader by Sik
author | Michael Pavone <pavone@retrodev.com> |
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date | Wed, 23 Aug 2023 21:38:39 -0700 |
parents | 0343f0d5add0 |
children | c76c81c21ae5 |
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#include <stdio.h> #include "rf5c164.h" enum { ENV, PAN, FDL, FDH, LSL, LSH, ST, CTRL, CHAN_ENABLE }; enum { START, NORMAL, LOOP }; #define FLAG_SOUNDING 0x80 #define FLAG_PENDING 0x01 void rf5c164_init(rf5c164* pcm, uint32_t mclks, uint32_t divider) { pcm->audio = render_audio_source("rf5c164", mclks, divider * 384, 2); pcm->clock_step = divider * 4; } void rf5c164_deinit(rf5c164* pcm) { render_free_source(pcm->audio); } void rf5c164_adjust_master_clock(rf5c164* pcm, uint32_t mclks) { render_audio_adjust_clock(pcm->audio, mclks, pcm->clock_step * 96); } //48 cycles per channel //1 external write per 16 cycles //3 external writes per channel/sample // TCE pulse width is 200ns @ 10Mhz aka 2 cycles // total cycle is longer than TCE pulse, guessing 4 cycles // 12 memory access slots per channel sample // 3 for external memory writes // 1 for internal register writes? // 1 for refresh? // 6 for register reads? // or maybe 7 for register reads and writes happen when register is read? #define CHECK pcm->cycle += pcm->clock_step; pcm->step++; if (pcm->cycle >= cycle) break #define CHECK_LOOP pcm->cycle += pcm->clock_step; pcm->step = 0; if (pcm->cycle >= cycle) break static void write_if_not_sounding(rf5c164* pcm) { if (!(pcm->flags & FLAG_SOUNDING) && (pcm->flags & FLAG_PENDING) && pcm->pending_address >= 0x1000) { pcm->ram[(pcm->pending_address & 0xFFF) | pcm->ram_bank] = pcm->pending_byte; pcm->flags &= ~FLAG_PENDING; } } static void write_always(rf5c164* pcm) { if ((pcm->flags & FLAG_PENDING) && pcm->pending_address >= 0x1000) { pcm->ram[(pcm->pending_address & 0xFFF) | pcm->ram_bank] = pcm->pending_byte; pcm->flags &= ~FLAG_PENDING; } } void rf5c164_run(rf5c164* pcm, uint32_t cycle) { //TODO: Timing of this is all educated guesses based on documentation, do some real measurements while (pcm->cycle < cycle) { switch (pcm->step) { case 0: //handle internal memory write // RF5C164 datasheet seems to suggest only 1 "internal memory" write every 48 cycles when the chip is not sounding (globally) // and 1 write every 384 cycles when the chip is sounding (globally). However, games seem to expect to be able to write faster than that // RF5C68 datasheet suggests internal memory writes are unrestricted regardless of sounding status /*if ((pcm->cur_channel == pcm->selected_channel || !(pcm->flags & FLAG_SOUNDING)) && (pcm->flags & FLAG_PENDING) && pcm->pending_address <= ST ) { printf("pcm_write commit chan %d, %X - %X @ %u\n", pcm->selected_channel, pcm->pending_address, pcm->pending_byte, pcm->cycle); pcm->channels[pcm->selected_channel].regs[pcm->pending_address] = pcm->pending_byte; pcm->flags &= ~FLAG_PENDING; }*/ write_if_not_sounding(pcm); CHECK; case 1: if ((pcm->flags & FLAG_SOUNDING) && !(pcm->channel_enable & (1 << pcm->cur_channel))) { if (pcm->channels[pcm->cur_channel].state == START) { pcm->channels[pcm->cur_channel].cur_ptr = pcm->channels[pcm->cur_channel].regs[ST] << 19; //printf("chan %d START %X (%X raw)\n", pcm->cur_channel, pcm->channels[pcm->cur_channel].cur_ptr >> 11, pcm->channels[pcm->cur_channel].cur_ptr); pcm->channels[pcm->cur_channel].state = NORMAL; pcm->channels[pcm->cur_channel].trigger = 1; } else if (pcm->channels[pcm->cur_channel].state == LOOP) { uint32_t old_ptr = pcm->channels[pcm->cur_channel].cur_ptr; pcm->channels[pcm->cur_channel].cur_ptr = (pcm->channels[pcm->cur_channel].regs[LSH] << 19) | (pcm->channels[pcm->cur_channel].regs[LSL] << 11); //printf("chan %d LOOP %X (%X raw)\n", pcm->cur_channel, pcm->channels[pcm->cur_channel].cur_ptr >> 11, pcm->channels[pcm->cur_channel].cur_ptr); pcm->channels[pcm->cur_channel].state = NORMAL; pcm->channels[pcm->cur_channel].trigger = old_ptr != pcm->channels[pcm->cur_channel].cur_ptr; } else { pcm->channels[pcm->cur_channel].trigger = 0; } } write_if_not_sounding(pcm); CHECK; case 2: { if ((pcm->flags & FLAG_SOUNDING) && !(pcm->channel_enable & (1 << pcm->cur_channel))) { uint8_t byte = pcm->ram[pcm->channels[pcm->cur_channel].cur_ptr >> 11]; if (byte == 0xFF) { pcm->channels[pcm->cur_channel].state = LOOP; } else { pcm->channels[pcm->cur_channel].sample = byte; } } write_if_not_sounding(pcm); CHECK; } case 3: write_always(pcm); CHECK; case 4: if ((pcm->flags & FLAG_SOUNDING) && !(pcm->channel_enable & (1 << pcm->cur_channel))) { pcm->channels[pcm->cur_channel].cur_ptr += (pcm->channels[pcm->cur_channel].regs[FDH] << 8) | pcm->channels[pcm->cur_channel].regs[FDL]; pcm->channels[pcm->cur_channel].cur_ptr &= 0x7FFFFFF; } write_if_not_sounding(pcm); CHECK; case 5: write_if_not_sounding(pcm); CHECK; case 6: write_if_not_sounding(pcm); CHECK; case 7: write_always(pcm); CHECK; case 8: write_if_not_sounding(pcm); CHECK; case 9: if ((pcm->flags & FLAG_SOUNDING) && !(pcm->channel_enable & (1 << pcm->cur_channel))) { int16_t sample = pcm->channels[pcm->cur_channel].sample & 0x7F; if (!(pcm->channels[pcm->cur_channel].sample & 0x80)) { sample = -sample; } sample *= pcm->channels[pcm->cur_channel].regs[ENV]; int16_t left = (sample * (pcm->channels[pcm->cur_channel].regs[PAN] >> 4)) >> 5; int16_t right = (sample * (pcm->channels[pcm->cur_channel].regs[PAN] & 0xF)) >> 5; //printf("chan %d, raw %X, sample %d, left %d, right %d, ptr %X (raw %X)\n", pcm->cur_channel, pcm->channels[pcm->cur_channel].sample, sample, left, right, pcm->channels[pcm->cur_channel].cur_ptr >> 11, pcm->channels[pcm->cur_channel].cur_ptr); #ifndef IS_LIB if (pcm->scope) { scope_add_sample(pcm->scope, pcm->channels[pcm->cur_channel].scope_channel, sample, pcm->channels[pcm->cur_channel].trigger); } #endif pcm->left += left; pcm->right += right; #ifdef IS_LIB } #else } else if (pcm->scope) { scope_add_sample(pcm->scope, pcm->channels[pcm->cur_channel].scope_channel, 0, 0); } #endif write_if_not_sounding(pcm); CHECK; case 10: //refresh? //does refresh happen at the same rate when sounding disabled? warning in sega docs suggests maybe not write_if_not_sounding(pcm); CHECK; case 11: write_always(pcm); pcm->cur_channel++; pcm->cur_channel &= 7; if (!pcm->cur_channel) { if (pcm->left > INT16_MAX) { pcm->left = INT16_MAX; } else if (pcm->left < INT16_MIN) { pcm->left = INT16_MIN; } if (pcm->right > INT16_MAX) { pcm->right = INT16_MAX; } else if (pcm->right < INT16_MIN) { pcm->right = INT16_MIN; } render_put_stereo_sample(pcm->audio, pcm->left, pcm->right); pcm->left = pcm->right = 0; } CHECK_LOOP; } } } void rf5c164_write(rf5c164* pcm, uint16_t address, uint8_t value) { //printf("pcm_write %X - %X @ %u\n", address, value, pcm->cycle); if (address == CTRL) { pcm->flags &= ~FLAG_SOUNDING; pcm->flags |= value & FLAG_SOUNDING; if (value & 0x40) { pcm->selected_channel = value & 0x7; //printf("selected channel %d\n", pcm->selected_channel); } else { pcm->ram_bank = value << 12 & 0xF000; //printf("selected RAM bank %X\n", pcm->ram_bank); } if (!(pcm->flags & FLAG_SOUNDING)) { pcm->left = pcm->right = 0; } } else if (address == CHAN_ENABLE) { uint8_t changed = pcm->channel_enable ^ value; pcm->channel_enable = value; for (int i = 0; i < 8; i++) { int mask = 1 << i; if ((changed & mask) && !(mask & value)) { pcm->channels[i].state = START; } } } else if (address <= ST) { //See note in first step of rf5c164_run pcm->channels[pcm->selected_channel].regs[address] = value; } else if (address > 0x1000){ pcm->pending_address = address; pcm->pending_byte = value; pcm->flags |= FLAG_PENDING; } } uint8_t rf5c164_read(rf5c164* pcm, uint16_t address) { if (address >= 0x10 && address < 0x20) { uint16_t chan = address >> 1 & 0x7; if (address & 1) { return pcm->channels[chan].cur_ptr >> 19; } else { return pcm->channels[chan].cur_ptr >> 11; } } else if (address >= 0x1000 && !(pcm->flags & FLAG_SOUNDING)) { return pcm->ram[pcm->ram_bank | (address & 0xFFF)]; } else { return 0xFF; } } void rf5c164_enable_scope(rf5c164* pcm, oscilloscope *scope) { #ifndef IS_LIB static const char *names[] = { "Richo #1", "Richo #2", "Richo #3", "Richo #4", "Richo #5", "Richo #6", "Richo #7", "Richo #8", }; pcm->scope = scope; for (int i = 0; i < 8; i ++) { pcm->channels[i].scope_channel = scope_add_channel(scope, names[i], 50000000 / (pcm->clock_step * 96)); } #endif } void rf5c164_serialize(rf5c164* pcm, serialize_buffer *buf) { save_int32(buf, pcm->cycle); save_buffer16(buf, pcm->ram, sizeof(pcm->ram)/sizeof(*pcm->ram)); save_int16(buf, pcm->ram_bank); save_int16(buf, pcm->pending_address); save_int32(buf, pcm->left); save_int32(buf, pcm->right); for (int i = 0; i < 8; i++) { rf5c164_channel *chan = pcm->channels + i; save_int32(buf, chan->cur_ptr); save_buffer8(buf, chan->regs, sizeof(chan->regs)); save_int8(buf, chan->sample); } save_int8(buf, pcm->pending_byte); save_int8(buf, pcm->channel_enable); save_int8(buf, pcm->selected_channel); save_int8(buf, pcm->cur_channel); save_int8(buf, pcm->step); save_int8(buf, pcm->flags); } void rf5c164_deserialize(deserialize_buffer *buf, void *vpcm) { rf5c164 *pcm = vpcm; pcm->cycle = load_int32(buf); load_buffer16(buf, pcm->ram, sizeof(pcm->ram)/sizeof(*pcm->ram)); pcm->ram_bank = load_int16(buf); pcm->pending_address = load_int16(buf); pcm->left = load_int32(buf); pcm->right = load_int32(buf); for (int i = 0; i < 8; i++) { rf5c164_channel *chan = pcm->channels + i; chan->cur_ptr = load_int32(buf); load_buffer8(buf, chan->regs, sizeof(chan->regs)); chan->sample = load_int8(buf); } pcm->pending_byte = load_int8(buf); pcm->channel_enable = load_int8(buf); pcm->selected_channel = load_int8(buf); pcm->cur_channel = load_int8(buf); pcm->step = load_int8(buf); pcm->flags = load_int8(buf); }