Summing up time deltas is SHIT

code.py

@@ -8,10 +8,11 @@ import board
 import busio
 import adafruit_midi
 
-from adafruit_midi.control_change import ControlChange
+# 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():
@@ -33,71 +34,84 @@ def init():
 def trig(note_nr):
     # print("trig: " + str(note_nr))
     midi.send(NoteOn(note_nr, 127))
-    midi.send(NoteOff(note_nr, 0))
-
-
-def subdiv(clk_bar, clk_bar_old, div, note_nr):
-    div_ns = div_to_ns(div)
-    clk_sub1_old = clk_bar_old % div_ns
-    clk_sub1 = clk_bar % div_ns
-    clk_sub1_diff = clk_sub1 - clk_sub1_old
-    if clk_sub1_diff < 0:
-        trig(note_nr)
-        # note_buffer_on.append(NoteOn(note_nr, 127))
-        # note_buffer_off.append(NoteOff(note_nr, 127))
+    # MD doesnt need note off
+    # midi.send(NoteOff(note_nr, 0))
 
 
-def div_to_ns(div) -> int:
-        # trig(note_nr)
+def div_to_ns(div):
+    # trig(note_nr)
     clk_pulse_per_second = 1000000000
     beat_per_bar = 4
-    bar_ns = beat_per_bar / bpm * 60 * clk_pulse_per_second
+    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]
+    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):
+    for i in range(1, 16 + 1):
         trig(md_note(i))
-        time.sleep(0.2)
+        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")
-    bar_ns = div_to_ns(1)
-
-    clk_bar = time.monotonic_ns() % bar_ns
-    while True:
-        clk_bar_old = clk_bar
-        clk_bar = time.monotonic_ns() % bar_ns
+    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))
 
-        # md_selftest()
-
-        # for i in range(1,16+1):
-        #     subdiv(clk_bar, clk_bar_old, i, md_note(i))
-        subdiv(clk_bar, clk_bar_old, 1, md_note(1))
-        subdiv(clk_bar, clk_bar_old, 8, md_note(2))
-
-
-        # for i in note_buffer_on:
-        #     midi.send(i)
-        #
-        # for i in note_buffer_off:
-        #     midi.send(i)
-        #
-        # note_buffer_on.clear()
-        # note_buffer_off.clear()
-
-bpm = 120
-note_buffer_on = []
-note_buffer_off = []
 
 init()
 main()