Swagbadge2021 SoftwareDev

Want to write your own programs to run on your badge? This page gives a brief overview of the software architecture, an example of a program, and a reference guide on how to access the hardware.

Background

The badge runs MicroPython (written by Damien George from Melbourne!) and has the Aiko framework (written by OHMC's Andy Gelme) loaded on it.

MicroPython gives you libraries to access the ESP32 microprocessor functionality. Things like: reading and writing to specific pins on the processor or performing operating system functions such as accessing the file system).

Aiko gives you convenience libraries for driving the badge hardware like the OLED screens, as well as running threads to keep your badge connected to wifi, a connection to the MQTT server, the emergency-stop function to prevent runaway code, and an automatic upgrade function so we can ship upgrades to your device without you having to wrangle git.

Sample code

This code writes "Hello world" to one screen, while displaying the status of the wifi, MQTT connection, button presses and slider status on the left hand screen.

It demonstrates how to use the Aiko event loop to periodically poll for hardware state, as well as how to access some of the features of the badge.

You can find more example code in the ```examples``` directory of the Aiko repository on github.

Example code: use "expand" to expand

 
# examples/helloworld.py
#
# Writes a message to the oled and displays some state info
#
# Usage
# ~~~~~
# import examples.helloworld as helloworld
# from examples.helloworld import run
# run()
#

from machine import Pin, TouchPad
import aiko.event as event
import aiko.oled as oled

title = "Hello!"

import configuration.main


# Buttons: underneath the screens
button_right = Pin(17, Pin.IN, Pin.PULL_UP)
button_left = Pin(16, Pin.IN, Pin.PULL_UP)

# Clean out the whole line that was there before
# Write some new text and show it
def oled_write_line(oled_target, x, y, text):
    oled_target.fill_rect(0,y,oled.width, oled.font_size, oled.bg)
    oled_target.text(text, x, y)
    oled_target.show()
    
def status():
    sliders = touch_slider_handler()
    oledL = oled.oleds[0]
    oledR = oled.oleds[1]
    oled.write_line(oledR, 1, 10, "Hello world!")
    oled_write_line(oledL, 1, 10, "Wifi: "+str(net.is_connected()))
    oled_write_line(oledL, 1, 20, "MQTT: "+str(mqtt.is_connected()))
    oled_write_line(oledL, 1, 30, " "+str(int(not(buttonL.value())))+" Button "+str(int(not(buttonR.value()))))


# Check on the status of the badge hardware and display that every 500ms          
def run():
    oled.oleds_clear(oled.bg)
    oled.set_title(title)
    event.add_timer_handler(status, 500)
    try:
        event.loop()
    finally:
        event.remove_timer_handler(statusbar)

Software reference

MicroPython environment

• lib path
• filesystem/module includes