void USART1_IRQHandler(void)
{
if (USART_GetITStatus(CEREAL_USARTx, USART_IT_RXNE) != RESET)
{
uint8_t c = cereal_rx_raw();
if (!ringbuffer_isfull(&cereal_incoming))
{
ringbuffer_push(&cereal_incoming, c);
if (c == 0 || c == '\r' || c == '\n') {
cereal_incoming.flag = 1;
}
}
else
{
cereal_incoming.flag = 1;
}
}
if (USART_GetITStatus(CEREAL_USARTx, USART_IT_TXE) != RESET )
{
#ifdef ENABLE_CEREAL_BUFFERED_TX
if (!ringbuffer_isempty(&cereal_outgoing)) {
cereal_tx_raw(ringbuffer_pop(&cereal_outgoing));
}
else {
cereal_outgoing.flag = 0;
USART_ITConfig(CEREAL_USARTx, USART_IT_TXE, DISABLE);
}
#endif
}
}
void cereal_wait()
{
#ifdef ENABLE_CEREAL_BUFFERED_TX
while (ringbuffer_isfull(&cereal_outgoing)) ;
#else
while (USART_GetFlagStatus(CEREAL_USARTx, USART_FLAG_TXE) == RESET) ;
#endif
}
void cereal_tx(uint8_t x)
{
#ifdef ENABLE_CEREAL_BUFFERED_TX
if (!ringbuffer_isfull(&cereal_outgoing))
{
ringbuffer_push(&cereal_outgoing, x);
if (cereal_outgoing.flag == 0) {
cereal_tx_raw(ringbuffer_pop(&cereal_outgoing));
cereal_outgoing.flag = 1;
USART_ITConfig(CEREAL_USARTx, USART_IT_TXE, ENABLE);
}
}
#else
cereal_tx_raw(x);
while (USART_GetFlagStatus(CEREAL_USARTx, USART_FLAG_TXE) == RESET) ;
#endif
}
static void soundcard_tick(int cyclesexecuted, bool behind) {
static int carry = 0;
//if (!active) {
// return;
//}
int total = cyclesexecuted + carry;
carry = total % TICKSPERSAMPLE;
int ticks = total - carry;
int samples = ticks / TICKSPERSAMPLE;
//log_println(LEVEL_INFO, TAG, "executed %d carry %d ticks %d samples %d", cyclesexecuted, carry, ticks, samples);
if (samples == 0)
return;
SDL_LockAudio();
for (int i = 0; i < samples; i++) {
masterchannel* master = &(channels[0].master);
if (master->config && SOUND_CHANNEL_ENABLED) { // sound is enabled
int16_t leftSample = 0;
int16_t rightSample = 0;
for (int i = 1; i < TOTALCHANNELS; i++) {
if (channels[i].audio.config & SOUND_CHANNEL_ENABLED) {
// channel ran out of samples.. so latch it again
audiochannel* chan = &(channelslatched[i].audio);
if (chan->samplepos == chan->samplelength) {
channelslatched[i] = channels[i];
chan = &(channelslatched[i].audio);
}
int page = (chan->config & SOUND_CHANNEL_PAGE)
>> SOUND_CHANNEL_PAGE_SHIFT;
uint32_t pageoffset = SAMPLEPAGESIZE * page;
uint32_t sampleoffset = pageoffset + chan->samplepointer
+ (chan->samplepos * 2);
// LEFT
if (chan->config & SOUND_CHANNEL_LEFT) {
//audiobuffer[bufferindex] = soundcard_mixsamples(audiobuffer[bufferindex],
// READ_WORD(sampleram, sampleoffset), VOLLEFT(chan->volume));
leftSample = READ_WORD(sampleram, sampleoffset);
}
// RIGHT
if (chan->config & SOUND_CHANNEL_RIGHT) {
//rightSample = soundcard_mixsamples(rightSample, READ_WORD(sampleram, sampleoffset),
// VOLRIGHT(chan->volume));
rightSample = READ_WORD(sampleram, sampleoffset);
}
// chan is all out of samples..
chan->samplepos++;
if (chan->samplepos == chan->samplelength) {
if (chan->config & SOUND_CHANNEL_INTERRUPT) {
chan->config |= SOUND_CHANNEL_RELOAD;
board_raise_interrupt(&soundcard);
}
}
}
}
// Adjust the output to the master volume.
//audiobuffer[bufferindex] *= VOLLEFT(master->volume) / UINT8_MAX;
//audiobuffer[bufferindex + 1] *= VOLLEFT(master->volume) / UINT8_MAX;
ringbuffer_put(audiobuffer, leftSample);
ringbuffer_put(audiobuffer, rightSample);
// we have caught up with the output
if (ringbuffer_isfull(audiobuffer)) {
log_println(LEVEL_INFO, TAG, "audio buffer has overflown");
break;
}
}
