todbot

# qteye_picodvi.py - qteye.py but on a PicoDVI RP2040 board
# 19 May 2024 - @todbot, on a DJDevon3 suggestion in Discord
# 23 Oct 2022 - @todbot / Tod Kurt
# Part of https://github.com/todbot/CircuitPython_GC9A01_demos
# also see: https://twitter.com/todbot/status/1584309133263532033
#      and: https://twitter.com/todbot/status/1584309133263532033
# Copy this file as "code.py" and the two eyeball BMP files to CIRCUITPY drive
# To install needed libraries: "circup install adafruit_imageload"
#
# Video demo below as a comment to this gist

todbot

// esp32s3_i2s_simple_sine.ino
// demonstrate I2S on ESP32S3
// origally from guiguig on Discord: https://discord.com/channels/327254708534116352/422210663507558401/1240067408660795424
// video demo below in comment

#include <I2S.h>

#define BCK  16  // feather esp32s3 A2
#define DOUT 17  // feather esp32s3 A1
#define LCK  18  // feather esp32s3 A0

todbot

# raise_vs_return_code.py -- Attempt to estimate cost of exception raise vs return in CircuitPython
# 14 May 2024 - @todbot

import time
import random
import gc

num_runs = 50000

# functions that do a small amount of something but really nothing

todbot

# demonstrate odd usb.core.USBError with max3421e
# requires "adafruit_usb_host_midi_todbot" below, which adds timeout on read()s
# 12 May 2024 - @todbot
import displayio
displayio.release_displays()

import time
import board
import usb
import max3421e

todbot

# Demonstrate trying to use the USBError of usb.core.Device.read() as a
# "no bytes available" indicator. Unfortuately, it's VERY slow. 
# Or more likely, it's missing messages mid-parse. 
# 8 May 2024 - @todbot
#
# note, this requires two special libraries:
# - adafruit_usb_host_midi_hostreadhack
# - winterbloom_smolmidi_hostreadhack

import time

todbot

# waiting_for_midi_code.py -- I'm always blocking for midi
# 6 May 2024 - @todbot
# works on PicoDVI RP2040 Feather / DVI Cowbell / etc.
import time, math, random
import board
import displayio
import bitmaptools
from adafruit_display_text import bitmap_label as label

num_colors = 16  # how many colors for our bitmap, can't be over 16 for DVI

todbot

# demonstrate blocking of usb.core.Device.read() 
#  4 May 2024 - @todbot and @jedgarpark
"""
This sketch demonstrates how `device.read()` blocks infinitely, which is different from established behavior. 

The normal semantics of `device.read()` when using either `busio.UART` or `usb_midi.PortIn`
is that the read() does not noticably block if a `timeout` is given. 
(Explicitly in the constructor of `busio.UART` and apparently implicitly in just how `usb_midi` works)

But for the `usb.core.Device` that is returned (as demo'd below), the `device.read()` blocks forever. 

todbot

# SPDX-FileCopyrightText: Copyright (c) 2023 Scott Shawcroft for Adafruit Industries
# SPDX-FileCopyrightText: Copyright (c) 2024 Tod Kurt
#
# SPDX-License-Identifier: Unlicense
#
# Forward MIDI from device on USB Host port to computer via USB MIDI 
# and 5-pin serial MIDI via MIDI Feather Wing or similar MIDI output.
# Suppots hot-plug of the device on the USB Host port.
#
# adapted from https://github.com/adafruit/Adafruit_CircuitPython_USB_Host_MIDI/blob/main/examples/usb_host_midi_simpletest.py

todbot

# quick-n-dirty MIDI controller with Circuit Playground Express
# 30 Apr 2024 - @todbot / Tod Kurt
# Works on Circuit Playground Express in CircuitPython 9, 
#  but will also work on also any board with touchio, like Trinket M0 or QTPy M0
# Uses the minimal number of libraries to save RAM on the tiny M0 in the CPX
#  (e.g. cannot load `adafruit_circuitpython`, `adafruit_midi`, and `adafruit_debouncer` on CPX)

import board
import touchio
import usb_midi

todbot

// samd21 blink LED on PA10 on Trinket M0, controlled by button on D3 (PA07)
// adapted / stolen from:
// https://github.com/LifeWithDavid/RaspberryPiPico-BareMetalAdventures/blob/main/Chapter%2004/assembly.s
// with much help from https://www.whynotestflight.com/excuses/its-alive-samd21e18a-assembly-no-sdk/
    
.cpu cortex-m0
.syntax unified
.thumb

.global main                    // 'main' used in startup.s