diff --git a/presets/cpc/music.c b/presets/cpc/music.c
new file mode 100644
index 00000000..fa405d4b
--- /dev/null
+++ b/presets/cpc/music.c
@@ -0,0 +1,104 @@
+
+/*
+Demonstrates playing multi-voice music on the PSG
+using the CPC BIOS functions.
+
+Similar to the music example in "Making Arcade Games in C".
+*/
+
+#include <stdlib.h>
+#include <string.h>
+#include "cpctelera.h"
+
+#include "sound_bios.h"
+//#link "sound_bios.c"
+
+#include "music.h"
+
+typedef unsigned char byte;
+typedef unsigned short word;
+
+//
+// MUSIC ROUTINES
+//
+
+void music_start(const byte* music);
+void music_update();
+
+// Namespace(length=64, upper=49, freq=62500.0, bias=0, maxbits=12)
+// 430.0 4.526547151857908 49
+const int note_table[64] = {
+2464,2326,2195,2072,1956,1846,1742,1644,1552,1465,1383,1305,1232,1163,1098,1036,978,923,871,822,776,733,691,653,616,581,549,518,489,461,436,411,388,366,346,326,308,291,274,259,244,231,218,206,194,183,173,163,154,145,137,129,122,115,109,103,97,92,86,82,77,73,69,65,};
+
+struct {
+  byte volume;
+} voice[3];
+
+byte music_index = 0;
+byte cur_duration = 0;
+byte num_voices = 3;
+
+static const byte* music_ptr = NULL;
+
+inline byte next_music_byte() {
+  return *music_ptr++;
+}
+
+void music_update() {
+  byte ch;
+  byte freech = 0;
+  for (ch=0; ch<num_voices; ch++) {
+    if (voice[ch].volume) {
+      voice[ch].volume--;
+    } else {
+      freech = ch;
+    }
+  }
+  if (music_ptr) {
+    ch = freech;
+    while (cur_duration == 0) {
+      byte note = next_music_byte();
+      if ((note & 0x80) == 0) {
+        int period = note_table[note & 63];
+        sound(ch+1, period, 5, 15, 1, 0, 0);
+        voice[ch].volume = 31;
+        ch = ch ? ch-1 : num_voices-1;
+      } else {
+        if (note == 0xff)
+          music_ptr = NULL;
+        cur_duration = note & 63;
+      }
+    }
+    cur_duration--;
+  }
+}
+
+void music_start(const byte* music) __critical {
+  music_ptr = music;
+  cur_duration == 0;
+}
+
+///
+/// MUSIC TEST
+///
+
+#ifdef __MAIN__
+
+const byte music1[] = {
+0x38,0x8c,0x3a,0x88,0x20,0x81,0x23,0x82,0x28,0x81,0x3b,0x32,0x2c,0xa4,0x3a,0x8c,0x38,0x32,0x2c,0x91,0x1f,0x83,0x22,0x83,0x27,0x81,0x37,0x31,0x2e,0xa4,0x35,0x2c,0x8c,0x37,0x31,0x2e,0x90,0x20,0x83,0x23,0x83,0x27,0x82,0x38,0x2f,0x27,0xbf,0x85,0x20,0x81,0x23,0x82,0x27,0x81,0x38,0x2f,0x27,0xb0,0x2c,0x2c,0x20,0x98,0x2f,0x2c,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x20,0x8c,0x31,0x2e,0x27,0x98,0x33,0x2f,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x34,0x31,0x20,0x8c,0x33,0x2f,0x27,0x98,0x31,0x2e,0x2a,0x8c,0x1e,0x8c,0x22,0x8c,0x1e,0x8c,0x2e,0x2a,0x25,0x98,0x2a,0x2a,0x2a,0x8c,0x1e,0x8c,0x22,0x8c,0x2c,0x2c,0x29,0x8c,0x2e,0x2e,0x28,0x98,0x2f,0x2c,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x20,0x8c,0x2c,0x27,0x23,0x98,0x2c,0x26,0x23,0x8c,0x1c,0x8c,0x23,0x8c,0x2b,0x22,0x20,0x8c,0x2c,0x26,0x20,0x98,0x2e,0x27,0x1f,0x8c,0x1b,0x8c,0x1f,0x8c,0x1b,0x8c,0x22,0x8c,0x1f,0x8c,0x27,0x27,0x1f,0x8c,0x22,0x8c,0x2b,0x98,0x2c,0x2c,0x20,0x98,0x2f,0x2c,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x20,0x8c,0x31,0x2e,0x27,0x98,0x33,0x2f,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x34,0x31,0x20,0x8c,0x33,0x2f,0x27,0x98,0x31,0x2e,0x2a,0x8c,0x1e,0x8c,0x22,0x8c,0x1e,0x8c,0x2e,0x2a,0x25,0x98,0x2a,0x2a,0x2a,0x8c,0x1e,0x8c,0x22,0x8c,0x2c,0x2c,0x29,0x8c,0x2e,0x2e,0x28,0x98,0x2f,0x2c,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x2e,0x25,0x20,0x8c,0x2c,0x27,0x23,0x98,0x2b,0x27,0x22,0x8c,0x1b,0x8c,0x22,0x8c,0x29,0x20,0x1f,0x8c,0x2b,0x27,0x22,0x98,0x2c,0x27,0x23,0x8c,0x1b,0x8c,0x20,0x8c,0x1b,0x8c,0x27,0x8c,0x23,0x8c,0x2c,0x27,0x23,0x8c,0x1b,0x8c,0x20,0x8c,0x22,0x8c,0x23,0x8c,0x27,0x8c,0x36,0x33,0x2a,0x8c,0x23,0x8c,0x2a,0x8c,0x27,0x8c,0x1e,0x8c,0x23,0x8c,0x36,0x33,0x2a,0x8c,0x27,0x8c,0x2a,0x8c,0x35,0x31,0x27,0x8c,0x33,0x2f,0x2a,0x8c,0x23,0x8c,0x31,0x2e,0x2a,0x8c,0x22,0x8c,0x2a,0x8c,0x25,0x8c,0x2e,0x2a,0x25,0x8c,0x22,0x8c,0x2a,0x2a,0x2a,0x8c,0x25,0x8c,0x2a,0x8c,0x2c,0x2c,0x29,0x8c,0x2e,0x2e,0x28,0x8c,0x22,0x8c,0x2f,0x2c,0x27,0x8c,0x23,0x8c,0x27,0x8c,0x23,0x8c,0x2c,0x27,0x23,0x8c,0x23,0x8c,0x2c,0x26,0x23,0x8c,0x23,0x8c,0x28,0x8c,0x2b,0x22,0x23,0x8c,0x2c,0x26,0x20,0x8c,0x23,0x8c,0x2e,0x27,0x1f,0x8c,0x1f,0x8c,0x22,0x8c,0x27,0x8c,0x2b,0x27,0x22,0x8c,0x1f,0x8c,0x27,0x27,0x27,0x8c,0x22,0x8c,0x27,0x8c,0x2b,0x8c,0x27,0x8c,0x22,0x8c,0x36,0x33,0x2a,0x8c,0x23,0x8c,0x27,0x8c,0x2a,0x8c,0x23,0x8c,0x27,0x8c,0x36,0x33,0x2a,0x8c,0x23,0x8c,0x27,0x8c,0x35,0x31,0x2a,0x8c,0x33,0x2f,0x2a,0x8c,0x27,0x8c,0x31,0x2e,0x2a,0x8c,0x22,0x8c,0x25,0x8c,0x2a,0x8c,0x2e,0x2a,0x25,0x8c,0x25,0x8c,0x2a,0x2a,0x2a,0x8c,0x22,0x8c,0x25,0x8c,0x2c,0x2c,0x29,0x8c,0x2e,0x2e,0x28,0x8c,0x22,0x8c,0x2f,0x2c,0x27,0x8c,0x23,0x8c,0x27,0x8c,0x2e,0x25,0x20,0x8c,0x2c,0x27,0x23,0x8c,0x23,0x8c,0x2b,0x27,0x22,0x8c,0x22,0x8c,0x27,0x8c,0x29,0x20,0x2b,0x8c,0x2b,0x27,0x22,0x8c,0x22,0x8c,0x2c,0x27,0x23,0x8c,0x23,0x8c,0x28,0x25,0x25,0x8c,0x20,0x8c,0x25,0x22,0x28,0x8c,0x25,0x8c,0x2c,0x27,0x23,0xb0,0x38,0x8c,0x3a,0x88,0x20,0x81,0x23,0x82,0x28,0x81,0x3b,0x32,0x2c,0xa4,0x3a,0x8c,0x38,0x32,0x2c,0x91,0x1f,0x83,0x22,0x83,0x27,0x81,0x37,0x31,0x2e,0xa4,0x35,0x2c,0x8c,0x37,0x31,0x2e,0x90,0x20,0x83,0x23,0x83,0x27,0x82,0x38,0x2f,0x27,0xbf,0x85,0x20,0x81,0x23,0x82,0x27,0x81,0x38,0x2f,0x27,0xb0,0x20,0x98,0x23,0x8c,0x1b,0x8c,0x23,0x8c,0x20,0x8c,0x25,0x27,0x98,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x28,0x20,0x8c,0x27,0x27,0x98,0x25,0x8c,0x1e,0x8c,0x22,0x8c,0x1e,0x8c,0x22,0x25,0x98,0x1e,0x8c,0x1e,0x8c,0x22,0x8c,0x20,0x1e,0x8c,0x22,0x25,0x98,0x23,0x8c,0x1b,0x8c,0x23,0x8c,0x20,0x8c,0x20,0x27,0x98,0x20,0x8c,0x1c,0x8c,0x23,0x8c,0x1f,0x20,0x8c,0x20,0x28,0x98,0x22,0x8c,0x1b,0x8c,0x1f,0x8c,0x1b,0x8c,0x22,0x8c,0x1f,0x8c,0x1b,0x27,0x8c,0x22,0x8c,0x2b,0x98,0x20,0x98,0x23,0x20,0x8c,0x1b,0x8c,0x23,0x8c,0x20,0x8c,0x25,0x27,0x98,0x27,0x8c,0x1b,0x8c,0x23,0x8c,0x28,0x20,0x8c,0x27,0x27,0x98,0x25,0x8c,0x1e,0x8c,0x22,0x8c,0x1e,0x8c,0x22,0x25,0x98,0x1e,0x8c,0x1e,0x8c,0x22,0x8c,0x20,0x1e,0x8c,0x22,0x25,0x98,0x23,0x8c,0x1b,0x8c,0x23,0x8c,0x22,0x20,0x8c,0x20,0x27,0x98,0x1f,0x8c,0x1b,0x8c,0x22,0x8c,0x1d,0x1f,0x8c,0x1f,0x27,0x98,0x20,0x8c,0x1b,0x8c,0x20,0x8c,0x1b,0x8c,0x27,0x8c,0x23,0x8c,0x20,0x20,0x8c,0x1b,0x8c,0x20,0x8c,0x22,0x8c,0x23,0x8c,0x27,0x8c,0x27,0x2a,0x20,0x8c,0x23,0x8c,0x2a,0x8c,0x27,0x8c,0x1e,0x8c,0x23,0x8c,0x27,0x2a,0x1e,0x8c,0x27,0x8c,0x2a,0x8c,0x29,0x25,0x27,0x8c,0x23,0x27,0x1e,0x8c,0x23,0x8c,0x25,0x22,0x1e,0x8c,0x22,0x8c,0x2a,0x8c,0x25,0x8c,0x22,0x1e,0x1e,0x8c,0x22,0x8c,0x1e,0x1e,0x8c,0x25,0x8c,0x2a,0x8c,0x20,0x25,0x8c,0x22,0x1f,0x8c,0x22,0x8c,0x23,0x20,0x8c,0x23,0x8c,0x27,0x8c,0x23,0x8c,0x20,0x20,0x8c,0x23,0x8c,0x20,0x1c,0x8c,0x23,0x8c,0x28,0x8c,0x1f,0x23,0x8c,0x20,0x20,0x8c,0x23,0x8c,0x22,0x1b,0x8c,0x1f,0x8c,0x22,0x8c,0x27,0x8c,0x1f,0x22,0x8c,0x1f,0x8c,0x1b,0x1f,0x8c,0x22,0x8c,0x27,0x8c,0x2b,0x8c,0x27,0x8c,0x22,0x8c,0x2a,0x27,0x1e,0x8c,0x23,0x8c,0x27,0x8c,0x2a,0x8c,0x23,0x8c,0x27,0x8c,0x27,0x2a,0x1e,0x8c,0x23,0x8c,0x27,0x8c,0x29,0x25,0x2a,0x8c,0x27,0x23,0x23,0x8c,0x27,0x8c,0x25,0x22,0x1e,0x8c,0x22,0x8c,0x25,0x8c,0x2a,0x8c,0x22,0x1e,0x22,0x8c,0x25,0x8c,0x1e,0x1e,0x8c,0x22,0x8c,0x25,0x8c,0x20,0x2a,0x8c,0x22,0x1f,0x8c,0x22,0x8c,0x23,0x20,0x8c,0x23,0x8c,0x27,0x8c,0x22,0x20,0x8c,0x20,0x2c,0x8c,0x23,0x8c,0x1f,0x1b,0x8c,0x22,0x8c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+};
+
+void delay(int n) {
+  while (n--) cpct_waitVSYNC();
+}
+
+void main(void) {
+  env(1, 25, 15, 1);
+  while (1) {
+    if (!music_ptr) music_start(music1);
+    music_update();
+    delay(6);
+  }
+}
+
+#endif
diff --git a/presets/cpc/music.h b/presets/cpc/music.h
new file mode 100644
index 00000000..81a1fb9b
--- /dev/null
+++ b/presets/cpc/music.h
@@ -0,0 +1,6 @@
+
+// call to start music
+void music_start(const unsigned char* music);
+
+// call once every N frames
+void music_update();
diff --git a/presets/cpc/sound_bios.c b/presets/cpc/sound_bios.c
new file mode 100644
index 00000000..8b376310
--- /dev/null
+++ b/presets/cpc/sound_bios.c
@@ -0,0 +1,243 @@
+
+// http://www.cpcmania.com/Docs/Programming/Sound_I.htm
+
+#pragma disable_warning 85 // unused parameter warning
+
+////////////////////////////////////////////////////////////////////////
+// Sound01.c
+// Mochilote - www.cpcmania.com
+////////////////////////////////////////////////////////////////////////
+#include <stdio.h>
+
+//Firmware requires it in the central 32K of RAM (0x4000 to 0xC000), move it as you need...
+#define SOUND_BUFF 0x4FF6 //9 bytes
+#define ENT_BUFF 0x4FE6 //16 bytes
+#define ENV_BUFF 0x4FD6 //16 bytes
+
+////////////////////////////////////////////////////////////////////////
+//sound
+////////////////////////////////////////////////////////////////////////
+unsigned char bQueue = 0;
+unsigned char sound(
+  unsigned char nChannelStatus,
+  int nTonePeriod,
+  int nDuration,
+  unsigned char nVolume,
+  char nVolumeEnvelope,
+  char nToneEnvelope, 
+  unsigned char nNoisePeriod)
+{
+  //This function uses 9 bytes of memory for sound buffer. Firmware requires it in the central 32K of RAM (0x4000 to 0xC000)
+  /*
+    The bytes required to define the sound are as follows
+    byte 0 - channel status byte
+    byte 1 - volume envelope to use
+    byte 2 - tone envelope to use
+    bytes 3&4 - tone period
+    byte 5 - noise period
+    byte 6 - start volume
+    bytes 7&8 - duration of the sound, or envelope repeat count 
+  */
+  
+  __asm
+    LD HL, #SOUND_BUFF
+
+    LD A, 4 (IX) ;nChannelStatus
+    LD (HL), A
+    INC HL
+
+    LD A, 10 (IX) ;nVolumeEnvelope
+    LD (HL), A
+    INC HL
+
+    LD A, 11 (IX) ;nToneEnvelope
+    LD (HL), A
+    INC HL
+
+    LD A, 5 (IX) ;nTonePeriod
+    LD (HL), A
+    INC HL
+    LD A, 6 (IX) ;nTonePeriod
+    LD (HL), A
+    INC HL
+
+    LD A, 12 (IX) ;nNoisePeriod
+    LD (HL), A
+    INC HL
+
+    LD A, 9 (IX) ;nVolume
+    LD (HL), A
+    INC HL
+
+    LD A, 7 (IX) ;nDuration
+    LD (HL), A
+    INC HL
+    LD A, 8 (IX) ;nDuration
+    LD (HL), A
+    INC HL
+
+    LD HL, #SOUND_BUFF
+    CALL #0xBCAA ;SOUND QUEUE
+  
+    LD HL, #_bQueue
+    LD (HL), #0
+    JP NC, _EndSound
+    LD (HL), #1
+    _EndSound:
+  __endasm;
+  
+  return bQueue;
+}
+////////////////////////////////////////////////////////////////////////
+
+
+////////////////////////////////////////////////////////////////////////
+//ent
+////////////////////////////////////////////////////////////////////////
+void ent(unsigned char nEnvelopeNumber, unsigned char nNumberOfSteps, char nTonePeriodOfStep, unsigned char nTimePerStep)
+{
+  //This function uses 16 bytes of memory for ent buffer. Firmware requires it in the central 32K of RAM (0x4000 to 0xC000)
+  
+  __asm
+    LD HL, #ENT_BUFF
+
+    LD A, #0x1
+    LD (HL), A
+    INC HL
+
+    LD A, 5 (IX) ;nNumberOfSteps
+    LD (HL), A
+    INC HL
+
+    LD A, 6 (IX) ;nTonePeriodOfStep
+    LD (HL), A
+    INC HL
+
+    LD A, 7 (IX) ;nTimePerStep
+    LD (HL), A
+    INC HL
+
+    LD A, 4 (IX) ;nEnvelopeNumber
+    LD HL, #ENT_BUFF
+    CALL #0xBCBF ;SOUND TONE ENVELOPE
+  __endasm;
+}
+////////////////////////////////////////////////////////////////////////
+
+
+////////////////////////////////////////////////////////////////////////
+//env
+////////////////////////////////////////////////////////////////////////
+void env(unsigned char nEnvelopeNumber, unsigned char nNumberOfSteps, char nSizeOfStep, unsigned char nTimePerStep)
+{
+  //This function uses 16 bytes of memory for env buffer. Firmware requires it in the central 32K of RAM (0x4000 to 0xC000)
+  
+  __asm
+    LD HL, #ENV_BUFF
+
+    LD A, #0x1
+    LD (HL), A
+    INC HL
+
+    LD A, 5 (IX) ;nNumberOfSteps
+    LD (HL), A
+    INC HL
+
+    LD A, 6 (IX) ;nSizeOfStep
+    LD (HL), A
+    INC HL
+
+    LD A, 7 (IX) ;nTimePerStep
+    LD (HL), A
+    INC HL
+
+    LD A, 4 (IX) ;nEnvelopeNumber
+    LD HL, #ENV_BUFF
+    CALL #0xBCBC ;SOUND AMPL ENVELOPE
+  __endasm;
+}
+////////////////////////////////////////////////////////////////////////
+
+
+////////////////////////////////////////////////////////////////////////
+//soundcheck
+////////////////////////////////////////////////////////////////////////
+unsigned char nSoundCheck = 0;
+unsigned char soundcheck(unsigned char nChannelStatus)
+{
+  __asm
+  LD A, 4 (IX) ;nChannelStatus
+  CALL #0xBCAD; SOUND CHECK
+  LD HL, #_nSoundCheck
+  LD (HL), A
+  __endasm;
+  
+  return (nSoundCheck & 0x80);
+}
+////////////////////////////////////////////////////////////////////////
+
+#ifdef __MAIN__
+
+////////////////////////////////////////////////////////////////////////
+//main
+////////////////////////////////////////////////////////////////////////
+main()
+{
+  int aSounds[12] = { 478, 451, 426, 402, 379, 358, 338, 319, 301, 284, 268, 253 };
+  int n = 0;
+
+  printf("1\n\r");
+
+  for(n=0; n < 12; n++)
+  {
+    while(!sound(1, aSounds[n], 20, 15, 0, 0, 0));
+  }
+
+  while(soundcheck(1));
+  printf("2\n\r");
+
+  ent(1, 20, -11, 1);
+  sound(1, 200, 20, 15, 0, 1, 0);
+
+  while(soundcheck(1));
+  printf("3\n\r");
+
+  ent(1, 20, -11, 1);
+  sound(1, 428, 10, 15, 0, 1, 0);
+
+  while(soundcheck(1));
+  printf("4\n\r");
+
+  env(1, 25, 15, 5);
+  ent(1, 25, 120, 6);
+  sound(1, 428, 25, 15, 1, 1, 14);
+
+  while(soundcheck(1));
+  printf("5\n\r");
+
+  sound(1, 200, 20, 15, 0, 0, 0);
+  
+  while(soundcheck(1));
+  printf("6\n\r");
+  
+  env(1, 10, 1, 100);
+  sound(1, 284, 1000, 1, 1, 0, 0);
+  
+  while(soundcheck(1));
+  printf("7\n\r");
+
+  ent(1, 100, 2, 2);
+  sound(1,284,200,15,0,1,0);
+  
+  while(soundcheck(1));
+  printf("8\n\r");
+
+  ent(1, 100, -2, 2);
+  sound(1, 284, 200, 15, 0, 1, 0);
+  
+  while(soundcheck(1));
+  
+  return 0;
+}
+
+#endif
diff --git a/presets/cpc/sound_bios.h b/presets/cpc/sound_bios.h
new file mode 100644
index 00000000..befd89c2
--- /dev/null
+++ b/presets/cpc/sound_bios.h
@@ -0,0 +1,23 @@
+
+unsigned char sound(
+  unsigned char nChannelStatus,
+  int nTonePeriod,
+  int nDuration,
+  unsigned char nVolume,
+  char nVolumeEnvelope,
+  char nToneEnvelope, 
+  unsigned char nNoisePeriod);
+
+void ent(
+  unsigned char nEnvelopeNumber,
+  unsigned char nNumberOfSteps,
+  char nTonePeriodOfStep,
+  unsigned char nTimePerStep);
+
+void env(
+  unsigned char nEnvelopeNumber,
+  unsigned char nNumberOfSteps,
+  char nSizeOfStep,
+  unsigned char nTimePerStep);
+
+unsigned char soundcheck(unsigned char nChannelStatus);
diff --git a/src/platform/cpc.ts b/src/platform/cpc.ts
index 4426487f..d0253154 100644
--- a/src/platform/cpc.ts
+++ b/src/platform/cpc.ts
@@ -11,6 +11,7 @@ const CPC_PRESETS = [
   {id:'easy_sprites.c', name:'Keyboard + Sprites (C)'},
   {id:'medium_scrolling.c', name:'Scrolling Text (C)'},
   {id:'siegegame.c', name:'Siege Game (C)'},
+  {id:'music.c', name:'Music Player (C)'},
   //{id:'sprite_demo.c', name:'Sprite Demo (C)'},
   //{id:'keyboard_redefine.c', name:'Keyboard Redefine (C)'},
 ];