Add the ability to interactively play music with a "tracker keyboard"

jopl.c

@@ -1,3 +1,4 @@
+#include <dir.h>
 #include "jorth.h"
 #include "adlib.h"
 #include "kbd.h"
@@ -24,6 +25,30 @@ static void f_quit() {
   DONE = 1;
 }
 
+struct ffblk findfile;
+void f_findfirst() {
+  int result = findfirst(TOP().s, &findfile, 0);
+  if (result == 0) {
+    PUSHS(findfile.ff_name);
+  } else {
+    PUSHU(0);
+  }
+}
+void f_findnext() {
+  int result = findnext(&findfile);
+  if (result == 0) {
+    PUSHS(findfile.ff_name);
+  } else {
+    PUSHU(0);
+  }
+}
+
+void f_keyWasPressed() {
+  int k = TOP().i;
+  TOP().i = keyWasPressed(k);
+  consumeKey(k);
+}
+
 void do_repl() {
   char buf[128];
 
@@ -35,7 +60,12 @@ void do_repl() {
   CDEF("quit", f_quit);
   CDEF("adlib!", f_adlib_write);
   CDEF("adlib@", f_adlib_read);
-
+  CDEF("findfile", f_findfirst);
+  CDEF("findnext", f_findnext);
+  CDEF("key-start", kbd_init);
+  CDEF("key-end", kbd_cleanup);
+  CDEF("key-debounce", kbd_debounce);
+  CDEF("key-pressed", f_keyWasPressed);
   f_loadfile("jopl.jor");
   ontick = f_lookupcp("ontick");
   timer_setcallback(timer_callback);

jopl.jor

@@ -146,6 +146,25 @@ var t2
 
 : ontick adlib@ 0x20 & if startt2 player then ;
 
+: files findfile begin dup while yield findnext repeat ;
+
+: keynote [ inline|
+44 b, 31 b, 45 b, 32 b, 46 b, 47 b, 34 b, 48 b, 35 b, 49 b, 36 b, 50 b,
+16 b, 3  b, 17 b, 4  b, 18 b, 19 b, 6  b, 20 b, 7  b, 21 b, 8  b, 22 b,
+23 b, 10 b, 24 b, 11 b, 25 b,
+|inline ] 0 29 for dup i + ub@ key-pressed if drop i 3 + rdrop rdrop ret then next
+  drop 51 key-pressed if 15 else 0 then ;
+
+: keyboard
+  key-start begin
+    key-debounce 1 key-pressed not while
+    keynote dup if octave @ 12 * + noteon else drop then
+    78 key-pressed if 1 octave +! then
+    74 key-pressed if -1 octave +! then
+    41 key-pressed if noteoff then
+    rest
+  repeat key-end ;
+
 :noname
   default
   startt2

kbd.h

@@ -6,6 +6,7 @@ extern volatile char kbd_triggered;
 
 void kbd_init();
 void kbd_debounce(); // call once per frame
+void kbd_cleanup();
 unsigned char kbd_wait();
 
 #define KEY_OFF 0