TM1638 LED&KEY based MIDI visualiser on the Raspberry Pi Pico

This evening I had some fun with @diyelectromusic’s SimpleMIDIDecoder MicroPython library and the TM1638 LED&KEY module. The display shows MIDI channel and note number and the LEDs light up depending on velocity.

This is running on the Raspberry Pi Pico and also requires mcauser’s TM1638 library. Here’s the (slightly rushed) code:

# MIDI note visualiser for Raspberry Pi Pico and  TM1638 LED&KEY module by @AxWax
#
# Demo: https://twitter.com/AxWax/status/1480659594342899713
#
# This is heavily based on and requires
# the SimpleMIDIDecoder library by @diyelectromusic, which can be found at
# https://diyelectromusic.wordpress.com/2021/06/13/raspberry-pi-pico-midi-channel-router/
# as well as the MicroPython TM1638 LED Driver library by mcauser from
# https://github.com/mcauser/micropython-tm1638
# 
# Wiring:
# serial midi input on GP1 (UART0 RX)
# TM1638    Pico
# VCC       3v3
# GND       GND
# STB       GP4
# CLK       GP3
# DIO       GP2

import machine
import time
import ustruct
import SimpleMIDIDecoder

from time import sleep_ms
from machine import Pin
import tm1638

# Initialise the LED & Key
tm = tm1638.TM1638(stb=Pin(4), clk=Pin(3), dio=Pin(2))

# Initialise the serial MIDI handling
uart = machine.UART(0,31250)

# MIDI callback routines
def doMidiNoteOn(ch, cmd, note, vel):
    tm.show("C."+str(ch)+" N."+str(note)+"        ")
    if vel == 0:
        tm.leds(0b00000000)
    elif vel <= 16:
        tm.leds(0b00000001)
    elif vel <= 32:
        tm.leds(0b00000011)
    elif vel <= 48:
        tm.leds(0b00000111)
    elif vel <= 64:
        tm.leds(0b00001111)
    elif vel <= 80:
        tm.leds(0b00011111)
    elif vel <= 96:
        tm.leds(0b00111111)
    elif vel <= 112:
        tm.leds(0b01111111)
    else:
        tm.leds(0b11111111)
    uart.write(ustruct.pack("bbb",cmd+ch-1,note,vel))

def doMidiNoteOff(ch, cmd, note, vel):
    tm.leds(0b00000000)
    tm.show("C."+str(ch)+" N."+str(note)+"        ")
    uart.write(ustruct.pack("bbb",cmd+ch-1,note,vel))

def doMidiThru(ch, cmd, d1, d2):
    if (d2 == -1):
        uart.write(ustruct.pack("bb",cmd+ch,d1))
    else:
        uart.write(ustruct.pack("bbb",cmd+ch,d1,d2))

md = SimpleMIDIDecoder.SimpleMIDIDecoder()
md.cbNoteOn (doMidiNoteOn)
md.cbNoteOff (doMidiNoteOff)
md.cbThru (doMidiThru)

# the loop
while True:
    # Check for MIDI messages
    if (uart.any()):
        md.read(uart.read(1)[0])