diff --git a/technomid.py b/technomid.py index ba6ba92..736c926 100644 --- a/technomid.py +++ b/technomid.py @@ -145,14 +145,35 @@ def generate(f: BinaryIO): bend = int(round((fnote - note) * 0x1000)) # Error is encoded as pitch bend return min(0x7F, note), min(0x1FFF, bend) + def parse_midi_note(note: str) -> int: + flat_sharp = 0 + octave = 3 + if len(note) > 1: + if note[1] == '-' or note[1].isnumeric(): + octave = int(note[1:]) + else: + flat_sharp = { "b": -1, "#": 1 }[note[1]] + if len(note) > 2: + octave = int(note[2:]) + + natural = { "C": 0, "D": 2, "E": 4, "F": 5, "G": 7, "A": 9, "B": 11 } + return natural[note[0]] + flat_sharp + (1 + octave) * 12 + def techno(length: int): timer = int(round((1000000 * 1260 / 88) / 12)) # Intel 8253 (PIC) clock in Mhz + # Music tables from disassembly phrase = [2, *[1, 0, 0] * 3] * 3 + [2, 3] + [0, 3] * 3 - freq_tbl = [5424, 2712, 2416, 2280] + note_tbl = ["A3", "A4", "B4", "C5"] mangler = 0x0404 mangler_inc = 76 # len(phrase) * 2 + # Convert note table to period + freq_from_note = lambda m: 440.0 * 2.0 ** ((m - 69) / 12.0) + period_from_freq = lambda f: int(round(timer / f)) + period_from_note = lambda s: period_from_freq(freq_from_note(parse_midi_note(s))) + freq_tbl = [period_from_note(note) for note in note_tbl] + yield 0, MIDIMetaTempo(int(round((1000000 * 0x80000) / timer))) # 16th note every two PIC ticks yield 0, MIDIProgramChange(0, 80) # Set GM patch to #81 "Lead 1 (Square)"