add code2.py (was stale on hd)

code2.py

@@ -0,0 +1,117 @@
+# MIDI Cable
+# Black - Data
+# White - VCC 3.3v
+# Brown - GND
+
+import time
+import board
+import busio
+import adafruit_midi
+
+# from adafruit_midi.control_change import ControlChange
+from adafruit_midi.note_off import NoteOff
+from adafruit_midi.note_on import NoteOn
+
+bpm = 120
+
+
+def init():
+    print("init")
+    global midi
+    uart = busio.UART(board.TX, board.RX, baudrate=31250, timeout=0.001)  # init UART
+    midi_in_channel = 2
+    midi_out_channel = 1
+    midi = adafruit_midi.MIDI(
+        midi_in=uart,
+        midi_out=uart,
+        in_channel=(midi_in_channel - 1),
+        out_channel=(midi_out_channel - 1),
+        debug=False,
+    )
+    print("Default output channel:", midi.out_channel + 1)
+
+
+def trig(note_nr):
+    # print("trig: " + str(note_nr))
+    midi.send(NoteOn(note_nr, 127))
+    # MD doesnt need note off
+    # midi.send(NoteOff(note_nr, 0))
+
+
+def div_to_ns(div):
+    # trig(note_nr)
+    clk_pulse_per_second = 1000000000
+    beat_per_bar = 4
+    bar_ns = 60 / bpm * beat_per_bar * clk_pulse_per_second
+    return bar_ns / div
+
+
+def md_note(nr):
+    '''1-16'''
+    md_notes = [36, 38, 40, 41, 43, 45, 47, 48, 50, 52, 53, 55, 57, 59, 60, 62]
+    nr = min(nr, 16)
+    nr = max(nr, 1)
+    return md_notes[nr - 1]
+
+
+def md_selftest():
+    for i in range(1, 16 + 1):
+        trig(md_note(i))
+        time.sleep(0.01)
+
+
+# NEW
+# Summing up time deltas is SHIT because of the drift caused by rounding errors,
+# TOGETHER with the worse part, the INTERFERENCE errors sum up as well
+# no load - 0.0223318ms / 44779.1Hz
+# 1 subdiv(1) - 0.041875ms / 23880.6Hz
+# 4 subdiv(1-8) - 0.112662ms / 8876.11Hz
+# 8 subdiv(1-8) - 0.159569ms / 6266.89Hz
+# 16 subdiv(1-16) - 27.792ms / 35.9816Hz
+
+def main():
+    print("main")
+    nr_tracks = 8
+
+    clk_now = time.monotonic_ns()
+
+    clk_last = []
+    clk_next = []
+    clk_inc = []
+
+    for i in range(0, nr_tracks):
+        clk_inc.append(div_to_ns(i+1))
+        clk_last.append(clk_now)
+        clk_next.append(clk_now + clk_inc[i] )
+
+    clk_inc[0] = div_to_ns(1)
+    clk_inc[1] = div_to_ns(2)
+    clk_inc[2] = div_to_ns(3)
+    clk_inc[3] = div_to_ns(4)
+    clk_inc[4] = div_to_ns(5)
+    clk_inc[5] = div_to_ns(6)
+    clk_inc[6] = div_to_ns(7)
+    clk_inc[7] = div_to_ns(8)
+
+    clk_start = time.monotonic_ns()
+    loop_count = 0
+    loop_amt = 10000000
+    # while True:
+    while loop_count < loop_amt:
+        clk_now = time.monotonic_ns()
+
+        for i in range(0, nr_tracks):
+            if clk_now >= clk_next[i]:
+                trig(md_note(i+1))
+                clk_last[i] = clk_now
+                clk_next[i] = clk_now + clk_inc[i]
+
+        loop_count += 1
+
+    clk_end = time.monotonic_ns()
+    ms_per_loop = (clk_end - clk_start) / loop_amt / 1000 / 1000
+    print("{}ms / {}Hz".format(ms_per_loop, 1000 / ms_per_loop))
+
+
+init()
+main()