void prepare_audio_track(uint16_t msu_track) {
/* open file, fill buffer */
char suffix[11];
f_close(&file_handle);
snprintf(suffix, sizeof(suffix), "-%d.pcm", msu_track);
strcpy((char*)file_buf, (char*)file_lfn);
strcpy(strrchr((char*)file_buf, (int)'.'), suffix);
DBG_MSU1 printf("filename: %s\n", file_buf);
if(f_open(&file_handle, (const TCHAR*)file_buf, FA_READ) == FR_OK) {
file_handle.cltbl = pcm_cltbl;
pcm_cltbl[0] = CLTBL_SIZE;
f_lseek(&file_handle, CREATE_LINKMAP);
f_lseek(&file_handle, 4L);
f_read(&file_handle, &msu_loop_point, 4, &msu_audio_bytes_read);
DBG_MSU1 printf("loop point: %ld samples\n", msu_loop_point);
ff_sd_offload=1;
sd_offload_tgt=1;
f_lseek(&file_handle, 8L);
set_dac_addr(0);
dac_pause();
dac_reset();
ff_sd_offload=1;
sd_offload_tgt=1;
f_read(&file_handle, file_buf, MSU_DAC_BUFSIZE, &msu_audio_bytes_read);
/* clear busy bit */
set_msu_status(0x00, 0x28); /* set no bits, reset audio_busy + audio_error */
} else {
f_close(&file_handle);
set_msu_status(0x08, 0x20); /* reset audio_busy, set audio_error */
}
}
static void stop()
{
f_close( &file );
puts("File closed.");
// wait until both buffers are empty
while(dac_busy_buffers() > 0);
dac_reset();
mp3_free();
aac_free();
state = STOPPED;
}
int msu1_loop() {
/* it is assumed that the MSU file is already opened by calling msu1_check(). */
set_dac_vol(0x00);
while(fpga_status() & 0x4000);
uint16_t dac_addr = 0;
uint16_t msu_addr = 0;
uint8_t msu_repeat = 0;
uint16_t msu_track = 0;
uint32_t msu_offset = 0;
fpga_status_prev = fpga_status();
fpga_status_now = fpga_status();
int msu_res;
/* set_msu_addr(0x0);
msu_reset(0x0);
ff_sd_offload=1;
sd_offload_tgt=2;
f_lseek(&msufile, 0L);
ff_sd_offload=1;
sd_offload_tgt=2;
f_read(&msufile, file_buf, 16384, &msu_data_bytes_read);
*/
set_dac_addr(dac_addr);
dac_pause();
dac_reset();
set_msu_addr(0x0);
msu_reset(0x0);
ff_sd_offload=1;
sd_offload_tgt=2;
f_lseek(&msufile, 0L);
ff_sd_offload=1;
sd_offload_tgt=2;
f_read(&msufile, file_buf, 16384, &msu_data_bytes_read);
prepare_audio_track(0);
prepare_data(0);
/* audio_start, data_start, 0, audio_ctrl[1:0], ctrl_start */
while((msu_res = msu1_check_reset()) == MSU_RESET_NONE){
cli_entrycheck();
fpga_status_now = fpga_status();
/* Data buffer refill */
if((fpga_status_now & 0x2000) != (fpga_status_prev & 0x2000)) {
DBG_MSU1 printf("data\n");
uint8_t pageno = 0;
if(fpga_status_now & 0x2000) {
msu_addr = 0x0;
msu_page1_start = msu_page2_start + msu_page_size;
pageno = 1;
} else {
msu_addr = 0x2000;
msu_page2_start = msu_page1_start + msu_page_size;
pageno = 2;
}
set_msu_addr(msu_addr);
sd_offload_tgt=2;
ff_sd_offload=1;
msu_res = f_read(&msufile, file_buf, 8192, &msu_data_bytes_read);
DBG_MSU1 printf("data buffer refilled. res=%d page1=%08lx page2=%08lx\n", msu_res, msu_page1_start, msu_page2_start);
}
/* Audio buffer refill */
if((fpga_status_now & 0x4000) != (fpga_status_prev & 0x4000)) {
if(fpga_status_now & 0x4000) {
dac_addr = 0;
} else {
dac_addr = MSU_DAC_BUFSIZE/2;
}
set_dac_addr(dac_addr);
sd_offload_tgt=1;
ff_sd_offload=1;
f_read(&file_handle, file_buf, MSU_DAC_BUFSIZE/2, &msu_audio_bytes_read);
}
if(fpga_status_now & 0x0020) {
/* get trackno */
msu_track = get_msu_track();
DBG_MSU1 printf("Audio requested! Track=%d\n", msu_track);
prepare_audio_track(msu_track);
}
if(fpga_status_now & 0x0010) {
/* get address */
msu_offset=get_msu_offset();
prepare_data(msu_offset);
}
if(fpga_status_now & 0x0001) {
if(fpga_status_now & 0x0004) {
msu_repeat = 1;
set_msu_status(0x04, 0x01); /* set bit 2, reset bit 0 */
DBG_MSU1 printf("Repeat set!\n");
} else {
msu_repeat = 0;
set_msu_status(0x00, 0x05); /* set no bits, reset bit 0+2 */
DBG_MSU1 printf("Repeat clear!\n");
}
if(fpga_status_now & 0x0002) {
DBG_MSU1 printf("PLAY!\n");
set_msu_status(0x02, 0x01); /* set bit 0, reset bit 1 */
dac_play();
} else {
DBG_MSU1 printf("PAUSE!\n");
set_msu_status(0x00, 0x03); /* set no bits, reset bit 1+0 */
dac_pause();
}
}
fpga_status_prev = fpga_status_now;
/* handle loop / end */
if(msu_audio_bytes_read < MSU_DAC_BUFSIZE / 2) {
ff_sd_offload=0;
sd_offload=0;
if(msu_repeat) {
DBG_MSU1 printf("loop\n");
ff_sd_offload=1;
sd_offload_tgt=1;
f_lseek(&file_handle, 8L+msu_loop_point*4);
ff_sd_offload=1;
sd_offload_tgt=1;
f_read(&file_handle, file_buf, (MSU_DAC_BUFSIZE / 2) - msu_audio_bytes_read, &msu_audio_bytes_read);
} else {
set_msu_status(0x00, 0x02); /* clear play bit */
dac_pause();
}
msu_audio_bytes_read = MSU_DAC_BUFSIZE;
}
}
f_close(&file_handle);
DBG_MSU1 printf("Reset ");
if(msu_res == MSU_RESET_LONG) {
f_close(&msufile);
DBG_MSU1 printf("to menu\n");
return 1;
}
DBG_MSU1 printf("game\n");
return 0;
}
