MicroPython

From Chalmers Robotförening

MicroPython

a software implementation of the Python 3 programming language, written in C, that is optimized to run on a microcontroller

Micropython-logo.svg.png https://docs.micropython.org/en/latest/pyboard/

NodeMCU Devkit

Nodemcu.jpg

  • ESP8266 a microcontroller from Espressif
  • Integrated WiFi
  • 80MHz clock speed

Install

Windows/Mac CP2102 virtual com port driver

If you're running Windows or Mac you may have to install the virtual com port driver.

https://www.silabs.com/products/development-tools/software/usb-to-uart-bridge-vcp-drivers

Firmware

http://docs.micropython.org/en/v1.8.2/esp8266/esp8266/tutorial/intro.html#deploying-the-firmware

http://micropython.org/download#esp8266 <syntaxhighlight lang="bash"> wget http://micropython.org/resources/firmware/esp8266-20171101-v1.9.3.bin pip install esptool esptool.py --port /dev/ttyUSB0 write_flash 0 esp8266-20171101-v1.9.3.bin </syntaxhighlight>

Connect through serial

<syntaxhighlight lang="bash"> screen /dev/ttyUSB0 115200 </syntaxhighlight> Stäng screen: Ctrl+A, k, y

Connect to WiFi

http://docs.micropython.org/en/v1.8.7/esp8266/esp8266/tutorial/network_basics.html

<syntaxhighlight lang="python"> import network

ap_if = network.WLAN(network.AP_IF) ap_if.disconnect()

sta_if = network.WLAN(network.STA_IF) sta_if.active(True)

sta_if.connect('SSID', 'password') </syntaxhighlight>

<syntaxhighlight lang="python"> sta_if.ifconfig() </syntaxhighlight>

HTTP GET

<syntaxhighlight lang="python"> import urequests response = urequests.get("http://tim.gremalm.se/hello") response.text response.close() </syntaxhighlight>


WS2812

http://docs.micropython.org/en/v1.8.2/esp8266/esp8266/tutorial/neopixel.html <syntaxhighlight lang="python"> from machine import Pin from neopixel import NeoPixel

np = NeoPixel(Pin(2), 3)

np[0] = (255, 0, 0) np[1] = (0, 128, 0) np[2] = (0, 0, 64) np.write() </syntaxhighlight>

Color conversion with HSL2GRB

https://gist.github.com/dries007/26a2f36770c28500b912b0ecf1276129 Makes it easier to work with colors. Send in argument hue, and get out RGB <syntaxhighlight lang="python"> def hsv_to_rgb(h, s, v): if s == 0.0: return v, v, v i = int(h*6.0) f = (h*6.0) - i p = v*(1.0 - s) q = v*(1.0 - s*f) t = v*(1.0 - s*(1.0-f)) i = i%6 if i == 0: return v, t, p if i == 1: return q, v, p if i == 2: return p, v, t if i == 3: return p, q, v if i == 4: return t, p, v if i == 5: return v, p, q </syntaxhighlight>

GPIO

https://docs.micropython.org/en/latest/esp8266/esp8266/tutorial/pins.html <syntaxhighlight lang="python"> from machine import Pin button = Pin(0) button = Pin(0, Pin.IN, Pin.PULL_UP) pin.value() </syntaxhighlight> [1] NodeMCUPinout.png

File system on flash

<syntaxhighlight lang="python"> import os os.listdir() os.remove('filename') </syntaxhighlight>

Connect through WEBrepl (websocket)

https://learn.adafruit.com/micropython-basics-esp8266-webrepl/access-webrepl

<syntaxhighlight lang="python"> import webrepl_setup </syntaxhighlight>

Use HTTP and not HTTPS when connecting to the websocket. HTTPS-version doesn't support connecting to HTTP websocket due to mixed content. http://micropython.org/webrepl/

ampy

https://github.com/adafruit/ampy

a file utility tool for MicroPython on ESP8266

Workshop resources