Data commit

Task/Musical-scale/Yabasic/musical-scale.basic

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+// Rosetta Code problem: http://rosettacode.org/wiki/Musical_scale
+// by Galileo, 03/2022
+
+sample_rate = 44100
+duration = 8
+dataLength = sample_rate * duration
+hdrSize = 44
+fileLen = dataLength + hdrSize - 8
+data 261.6, 293.6, 329.6, 349.2, 392.0, 440.0, 493.9, 523.3
+
+sub int_to_bytes(dato, long)
+    local dato$, esp, esp$, i
+
+    esp$ = "00000000"
+    dato$ = hex$(dato)
+    esp = long * 2
+    dato$ = right$(esp$ + dato$, esp)
+    for i = esp - 1 to 1 step -2
+        poke #fn, dec(mid$(dato$, i, 2))
+    next
+end sub
+
+fn = open("notesyab.wav", "wb")
+
+print #fn, "RIFF";
+int_to_bytes(fileLen, 4)
+print #fn, "WAVEfmt ";
+int_to_bytes(16, 4)             // length of format data (= 16)
+int_to_bytes(1, 2)              // type of format (= 1 (PCM))
+int_to_bytes(1, 2)              // number of channels (= 1)
+int_to_bytes(sample_rate, 4)    // sample rate
+int_to_bytes(sample_rate, 4)    // sample rate * bps(8) * channels(1) / 8 (= sample rate)
+int_to_bytes(1,2)               // bps(8) * channels(1) / 8  (= 1)
+int_to_bytes(8,2)               // bits per sample (bps) (= 8)
+print #fn, "data";
+int_to_bytes(dataLength, 4)     // size of data section
+
+for j = 1 to duration
+    read f
+    omega = 2 * PI * f
+    for i = 0 to dataLength/duration-1
+        y = 32 * sin(omega * i / sample_rate)
+        byte = and(y, 255)
+        poke #fn, byte
+    next
+next
+
+close(fn)
+
+if peek$("os") = "windows" then
+    system("notesyab.wav")
+else // Linux
+    system("aplay notesyab.wav")
+endif