From 8f3f380dedcb70afeb51ab13e294a95cd8faf31b Mon Sep 17 00:00:00 2001
From: d_m <d_m@plastic-idolatry.com>
Date: Mon, 21 Aug 2023 23:23:29 -0400
Subject: [PATCH] synth demo

---
 mksite.sh     |  2 +-
 synthdemo.tal | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+), 1 deletion(-)
 create mode 100644 synthdemo.tal

diff --git a/mksite.sh b/mksite.sh
index d809a00..86941cc 100755
--- a/mksite.sh
+++ b/mksite.sh
@@ -14,7 +14,7 @@ for NAME in about.txt asma.rom math32.tal test-math32.tal test-math32.py \
   wave.tal graph.tal arg.tal arg-demo.tal \
   deck.tal cards.tal card-sprites.tal mask-sprites.tal \
   testing.tal type-abc.tal tar.tal \
-  audio.md audio.txt \
+  audio.md audio.txt synthdemo.tal \
 ; do
     echo "-> $NAME"
     cp $NAME /var/www/plastic-idolatry.com/html/erik/nxu
diff --git a/synthdemo.tal b/synthdemo.tal
new file mode 100644
index 0000000..7cd8736
--- /dev/null
+++ b/synthdemo.tal
@@ -0,0 +1,66 @@
+( synth demo using new device )
+
+|30 @Audio  [
+    &vec $2                     ( callback vector )
+    &dur $2                     ( duration in ms )
+    &mode $1                    ( mode -- currently articulation )
+    &vol $1                     ( L/R volume 0-f )
+    &a $1                       ( envelope: attack, 10ms resolution )
+    &d $1                       ( envelope: decay, 10ms resolution )
+    &s $1                       ( envelope: sustain, 10ms resolution )
+    &r $1                       ( envelope: release, 10ms resolution )
+    &len $2                     ( waveform data length in bytes )
+    &addr $2                    ( waveform data address )
+    &detune $1                  ( fractional semitone detune )
+    &pitch $1                   ( MIDI pitch to play )
+]
+
+|0000
+    @step $2
+    @tempo $2
+
+|0100
+    #00bb .tempo STZ2
+    #ff .Audio/vol DEO
+    ;square .Audio/addr DEO2
+    #0002 .Audio/len DEO2
+    ;play .Audio/vec DEO2
+(    #00 .Audio/mode DEO )
+    #30 .Audio/mode DEO
+    #00 .Audio/a DEO
+    #01 .Audio/d DEO
+    #08 .Audio/s DEO
+    #08 .Audio/r DEO
+    ( fall-through )
+
+@play
+    .tempo LDZ2 .Audio/dur DEO2                       ( ; dur<-tempo )
+    .step LDZ2k DUP2 ;notes ADD2                      ( z^ step* notes+step* )
+    LDA .Audio/pitch DEO                              ( z^ step* ; pitch<-p )
+    INC2 DUP2 #0004 LTH2 ?&done                       ( z^ step+1* )
+    POP2 #0000                                        ( z^ 0* )
+    .tempo LDZ2k #0002 SUB2                           ( z^ 0* zt^ tempo-2* )
+    #ea60 OVR2 #0004 MUL2 DIV2                        ( z^ 0* zt^ tempo-2* bpm* )
+    emit-bpm                                          ( z^ 0* zt^ tempo-2* ; emit bpm )
+    ROT STZ2                                          ( z^ 0* ; zt<-tempo-2 )
+    &done ROT STZ2 BRK                                ( ; z<-step' )
+
+( @notes 21 21 22 23 )
+@notes 39 39 3b 3c
+
+@square ff 00
+
+@emit-bpm ( bpm* -> )
+    emit-dec2 #2018 DEO LIT "b #18 DEO LIT "p #18 DEO LIT "m #18 DEO #0a18 DEO JMP2r
+
+( emit a short as a decimal )
+@emit-dec2 ( n* -> )
+    LITr 00 ( n [0] )
+    &read ( n [k] )
+        #000a DIV2k STH2k MUL2 SUB2 STH2r INCr ( n%10 n/10 [k+1] )
+        DUP2 ORA ,&read JCN
+    POP2 ( top element was 0000 )
+    &write ( n0 n1 ... nk [k+1] )
+        NIP #30 ADD #18 DEO LITr 01 SUBr ( n0 ... n{k-1} [k] )
+        STHkr ,&write JCN
+    POPr JMP2r