synth: voice end fixup

Author: Anton-2

ports/rp2/sdio/sdio_voice.c

@@ -647,31 +647,29 @@ uint32_t sdio_voice_fill_chunk(sdio_voice_manager_t *manager)
     {
         sdio_voice_t *voice = &manager->voices[i];
 
-        if (voice->state == VOICE_INIT && voice->sectors_filled == RING_SIZE)
+        if (voice->state == VOICE_INIT && voice->sectors_filled >= RING_SIZE/2)
         {
             voice->state = VOICE_RUNNING;
         }
 
-        if (voice->state == VOICE_RUNNING)
+        if ((voice->state == VOICE_RUNNING) && (voice->adsr != NULL))
         {
-            if (voice->adsr != NULL)
+            // Generate ADSR envelope into amplitude_buffer (reused as q16_t scratch)
+            adsr_process_block(voice->adsr, (q16_t *)manager->amplitude_buffer,
+                                manager->chunk_size);
+            // Convert q16_t [0..0xFFFF] → Q1_14_t [0..0x3FFF] in-place
+            for (uint32_t j = 0; j < manager->chunk_size; j++)
             {
-                // Generate ADSR envelope into amplitude_buffer (reused as q16_t scratch)
-                adsr_process_block(voice->adsr, (q16_t *)manager->amplitude_buffer,
-                                   manager->chunk_size);
-                // Convert q16_t [0..0xFFFF] → Q1_14_t [0..0x3FFF] in-place
-                for (uint32_t j = 0; j < manager->chunk_size; j++)
-                {
-                    manager->amplitude_buffer[j] =
-                        (Q1_14_t)(((uint16_t *)manager->amplitude_buffer)[j] >> 2);
-                }
+                manager->amplitude_buffer[j] =
+                    (Q1_14_t)(((uint16_t *)manager->amplitude_buffer)[j] >> 4);
             }
+
             _voice_fill_bloc(voice, manager->amplitude_buffer,
                              manager->accumulator_buffer, manager->chunk_size);
             nb_active += 1;
         }
 
-        if (voice->state == VOICE_CANCEL && manager->active_voice_idx != (int)i)
+        if (((voice->state == VOICE_CANCEL) || (voice->state == VOICE_DONE)) && manager->active_voice_idx != (int)i)
         {
             voice->state = VOICE_FREE;
         }

ports/rp2/sdio/sdio_voice.h

@@ -8,7 +8,7 @@
 #include "sdio_adsr.h"
 
 //Number of bits to index ring buffer
-#define RING_BITS    12                              //   12   13
+#define RING_BITS    14                              //   12   13
 #define RING_BYTES   (1<<RING_BITS)                  // 4096 8192 bytes ring buffer
 #define RING_SAMPLES (RING_BYTES/sizeof(int16_t))    // 2048 4096 samples in ring
 #define RING_SIZE    (RING_BYTES/SDIO_BLOCK_SIZE)    //    8   16 sectors in ring
@@ -55,7 +55,7 @@ typedef struct Sample {
 
 
 // Number of samples in loop cache (half the ring buffer)
-#define LOOP_CACHE_SAMPLES (RING_SAMPLES)
+#define LOOP_CACHE_SAMPLES (RING_SAMPLES/2)
 
 // Voice structure, every counter / size is in sample
 typedef struct {