Prototyping live resampling of uxn samples

2 files changed, 14 insertions, 11 deletions

diff --git a/src/main.c b/src/main.c
index fc7dad1..a6fb761 100644
--- a/src/main.c
+++ b/src/main.c
@@ -112,6 +112,8 @@ screen_talk(Device *d, u8 b0, u8 w) {
     }
 }
 
+static u8 buf[KB(1)];
+
 static void
 audio_talk(Device *d, u8 b0, u8 w) {
         AudioChannel *c = &apu.chan_0;
@@ -126,14 +128,15 @@ audio_talk(Device *d, u8 b0, u8 w) {
                 c->n_samples = mempeek16(d->dat, 0xa);
                 c->samples = &d->mem[mempeek16(d->dat, 0xc)];
                 // Transform the samples from u8 to s8.
-                // for (size_t i = 0; i < c->n_samples; ++i) {
-                //     c->samples[i] = c->samples[i] + 0x80;
-                // }
+                for (size_t i = 0; i < c->n_samples; ++i) {
+                    buf[i] = (u8)c->samples[i] + 0x80;
+                }
+                c->samples = &buf;
                 // c->volume[0] = d->dat[0xe] >> 4;
                 // c->volume[1] = d->dat[0xe] & 0xf;
                 c->loop = !(d->dat[0xf] & 0x80);
                 c->pitch = d->dat[0xf] & 0x7f;
-            init_sound(c);
+            // init_sound(c);
             reset_sound(c);
         txt_printf("note: %d     \n", c->pitch);
                 // apu_start(c, mempeek16(d->dat, 0x8), d->dat[0xf] & 0x7f);
@@ -180,6 +183,9 @@ init_uxn(Uxn *u) {
     // Initialize PPU.
     initppu(&ppu, 30, 20, 0);
 
+    // Enable sound.
+    SOUND_STATUS = SOUND_ENABLE;
+
     // Copy rom to VM.
     memcpy(u->ram.dat + PAGE_PROGRAM, uxn_rom, sizeof(uxn_rom));
 
@@ -188,9 +194,9 @@ init_uxn(Uxn *u) {
     portuxn(u, 0x1, "console", console_talk);
     devscreen = portuxn(u, 0x2, "screen", screen_talk);
     devaudio = portuxn(u, 0x3, "audio0", audio_talk);
-    portuxn(u, 0x4, "---", nil_talk);
-    portuxn(u, 0x5, "---", nil_talk);
-    portuxn(u, 0x6, "---", nil_talk);
+    portuxn(u, 0x4, "audio1", audio_talk);
+    portuxn(u, 0x5, "audio2", audio_talk);
+    portuxn(u, 0x6, "audio3", audio_talk);
     portuxn(u, 0x7, "---", nil_talk);
         devctrl = portuxn(u, 0x8, "controller", nil_talk);
         devmouse = portuxn(u, 0x9, "mouse", nil_talk);
diff --git a/src/uxn/devices/apu.c b/src/uxn/devices/apu.c
index fbe7c3d..b2ccc18 100644
--- a/src/uxn/devices/apu.c
+++ b/src/uxn/devices/apu.c
@@ -172,7 +172,7 @@ reset_sound(AudioChannel *chan) {
 
     // Prepare DMA copy.
     dma_transfer_copy(SOUND_FIFO_A, chan->samples, 1, 1,
-            DMA_CHUNK_32 | DMA_REFRESH | DMA_REPEAT | DMA_ENABLE);
+            DMA_DST_FIXED | DMA_CHUNK_32 | DMA_REFRESH | DMA_REPEAT | DMA_ENABLE);
 
     // Timer 1 used to stop playing samples.
     u32 sample_duration = chan->n_samples;
@@ -196,9 +196,6 @@ u8 square_wave[] =  {
 
 void
 init_sound(AudioChannel *chan) {
-    // Enable sound.
-    SOUND_STATUS = SOUND_ENABLE;
-
     // chan->samples = &square_wave;
     // chan->n_samples = 2;
     // chan->samples = &samples;