Mercurial > repos > blastem

changeset 2435:b8d894f7f9dc

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fix playback of ADPCM blocks with an odd number of samples
author Michael Pavone <pavone@retrodev.com>
date Thu, 08 Feb 2024 21:05:49 -0800
parents 2ee25a487e2b
children f50b9ed42ebd
files pico_pcm.c
diffstat 1 files changed, 9 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- a/pico_pcm.c	Thu Feb 08 20:44:44 2024 -0800
+++ b/pico_pcm.c	Thu Feb 08 21:05:49 2024 -0800
@@ -157,11 +157,13 @@
 			case 0x40:
 				pcm->rate = (cmd & 0x3F);
 				pcm->samples = 256;
+				pcm->nibble_store = 0;
 				break;
 			case 0x80:
 				pcm->rate = (cmd & 0x3F);
 				//FIXME: this probably does not happen instantly
 				pcm->samples = pcm_fifo_read(pcm) + 1;
+				pcm->nibble_store = 0;
 				break;
 			case 0xC0:
 				//FIXME: this probably does not happen instantly
@@ -170,6 +172,7 @@
 				//      Is this correct behavior if it does work?
 				pcm->counter = pcm->rate = pcm_fifo_read(pcm) & 0x3F;
 				pcm->samples = (pcm_fifo_read(pcm) + 1) * ((cmd & 7) + 1);
+				pcm->nibble_store = 0;
 				break;
 			}
 		}
@@ -194,11 +197,17 @@
 
 void pico_pcm_data_write(pico_pcm *pcm, uint16_t value)
 {
+	if (pcm->fifo_read == pcm->fifo_write) {
+		puts("ADPCM fifo overflow");
+	}
 	if (pcm->fifo_read == sizeof(pcm->fifo)) {
 		pcm->fifo_read = pcm->fifo_write;
 	}
 	pcm->fifo[pcm->fifo_write++] = value >> 8;
 	pcm->fifo_write &= sizeof(pcm->fifo)-1;
+	if (pcm->fifo_read == pcm->fifo_write) {
+		puts("ADPCM fifo overflow");
+	}
 	pcm->fifo[pcm->fifo_write++] = value;
 	pcm->fifo_write &= sizeof(pcm->fifo)-1;
 }