====== MicroPython ======

[[iot:expressiv|Micropython Installation]]

==== MicroPython für ESP8266 / ESP32 ====
  * https://docs.micropython.org/en/latest/esp8266/general.html
  * https://docs.micropython.org/en/latest/esp32/quickref.html
  * https://docs.zerynth.com/latest/official/board.zerynth.nodemcu_esp32/docs/index.html


  * [[https://github.com/lvidarte/esp8266/wiki/MicroPython%3A-REPL|Getting a MicroPython REPL prompt]]

==== Develop for / with Micropython ====

  * https://learn.adafruit.com/micropython-basics-loading-modules/frozen-modules
  * https://github.com/micropython/micropython-lib
  * https://github.com/adafruit/circuitpython

==== Porting Micropython ====
  * https://docs.micropython.org/en/latest/develop/porting.html
  * https://www.snaums.de/informatik/porting-micropython-to-bare-metal-raspberry-pi.html
  * https://www.snaums.de/informatik/porting-micropython-to-the-raspberry-pi-part-2.html
  * https://forum.micropython.org/viewtopic.php?t=5779

==== Blink LED: ====

<code python>
from machine import Pin
from time import sleep

led = Pin(2, Pin.OUT) # sets PIN 2 as Output (most boards have an LED connected)

while True:
  led.value(not led.value())  # toggle LED status
  sleep(0.25)
</code>

==== LED Helligkeit per PWM regeln: ====

<code python>
from machine import Pin, PWM
from time import sleep

frequency = 5000 # Hz: can be a value between 0 and 78125
led = PWM(Pin(2), frequency)

while True:
  for duty_cycle in range(0, 1024): #can be a value between 0 and 1023 (100%)
    led.duty(duty_cycle)
    sleep(0.005)
</code>

Quelle: https://randomnerdtutorials.com/esp32-esp8266-pwm-micropython/
==== MQTT auf dem ESP32: ====
  * https://boneskull.com/micropython-on-esp32-part-2/
  * https://randomnerdtutorials.com/micropython-mqtt-esp32-esp8266/

<code python>
import network
from umqtt.robust import MQTTClient

sta_if = network.WLAN(network.STA_IF)
sta_if.active(True)
sta_if.connect('<YOUR SSID>', '<YOUR PASSWORD>')

client = MQTTClient('<CLIENT-ID>', '<BROKER>')
client.connect()
client.publish('<TOPIC>', '<BYTE_STRING>')
</code>

==== I2S Audio auf dem ESP32: ====

  * https://www.youtube.com/watch?v=UXt27kOokh0 - MicroPython I2S Audio with the ESP32
  * https://github.com/miketeachman/micropython-i2s-examples

==== BME280====

  * https://randomnerdtutorials.com/micropython-bme280-esp32-esp8266/

==== DHT11/22 (ESP32)====
  * https://randomnerdtutorials.com/micropython-esp32-esp8266-dht11-dht22-web-server/
<code python>
from machine import Pin
from time import sleep
import dht

PIN_NR = # define your PIN # here

sensor = dht.DHT22(Pin(PIN_NR))

while True:
   try:
      sensor.measure()
      temp = sensor.temperature()
      hum = sensor.humidity()
      if (isinstance(temp, float) and isinstance(hum, float)) or (isinstance(temp, int) and isinstance(hum, int)):
         msg = (b'{0:3.1f},{1:3.1f}'.format(temp, hum))
      print(msg)
   except OSError as e:
      print('Failed to read sensor.')
   sleep(2)
</code>


==== MicroPython to AWS-IOT ====

  * https://www.hackster.io/user3282664/micropython-to-aws-iot-cc1c20

==== Enthaltene Module (ESP32)====
<code python>
help('modules')

__main__          framebuf          socket            upip
_boot             gc                ssl               upip_utarfile
_onewire          hashlib           struct            upysh
_thread           heapq             sys               urandom
_webrepl          inisetup          time              ure
apa106            io                ubinascii         urequests
array             json              ucollections      uselect
binascii          machine           ucryptolib        usocket
btree             math              uctypes           ussl
builtins          micropython       uerrno            ustruct
cmath             neopixel          uhashlib          utime
collections       network           uhashlib          utimeq
dht               ntptime           uheapq            uzlib
ds18x20           onewire           uio               webrepl
errno             os                ujson             webrepl_setup
esp               random            umqtt/robust      websocket
esp32             re                umqtt/simple      websocket_helper
flashbdev         select            uos               zlib
</code>

==== Freien Speicher ermitteln ====
<code python>
>>> import gc
>>> gc.collect()
>>> gc.mem_free()
107488
>>> import micropython
>>> micropython.mem_info()
</code>