Prerequisites

Flash the appropriate MicroPython firmware onto your ESP8266 board. I recommend using Thonny, as it is a convenient IDE for MicroPython, comes packaged with Python, and offers out-of-the-box support for MicroPython. Uploading files is also straightforward.

Useful Commands

Use help() to list sample code.
Use help('modules') to view installed packages.

Simple LED Blinking Program

from machine import Pin
from time import sleep

led = Pin(2, Pin.OUT)

while True:
    led.value(not led.value())
    sleep(1)

Listing Files on Flash Memory

import uos
print(uos.listdir())

Enabling WebREPL

To enable WebREPL, open the boot.py file and uncomment the following line:

import webrepl

The default password for the WiFi Access Point is micropythoN.

Setting Up WebREPL

Connect via:

screen <PORT> 115200

Or, use the Thonny IDE. Then, run:

import webrepl_setup

Retrieve WiFi SSID

MicroPython v1.8.6-7-gefd0927 on 2016-11-10; ESP module with ESP8266
Type "help()" for more information.
>>> import network
>>> ap = network.WLAN(network.AP_IF)
>>> print(ap.config('essid'))
MicroPython-d0fa00

Change WiFi Access Point and Password

MicroPython v1.8.6-7-gefd0927 on 2016-11-10; ESP module with ESP8266
Type "help()" for more information.
>>> import network
>>> ap = network.WLAN(network.AP_IF)
>>> ap.active(True)
>>> ap.config(essid='MyESP8266', authmode=network.AUTH_WPA_WPA2_PSK, password='mypassword')
>>> print(ap.config('essid'))
MyESP8

Download the webrepl client: GitHub
Disconnect the USB to Serial converter from the computer.
Connect the computer to the WiFi Access Point of the ESP8266.
Open webrepl.html using Chrome or Firefox.
Connect via ws://192.168.4.1:8266.

Using ESPtool

Thonny uses esptool to communicate with ESP boards. If you prefer using it directly, use these commands:

Install esptool

pip install esptool

Write a Binary to the ESP

esptool --port COM4 write_flash 0x1000 my_app-0x01000.bin

Write to Multiple Flash Addresses

esptool --port COM4 write_flash 0x00000 my_app.elf-0x00000.bin 0x40000 my_app.elf-0x40000.bin

To run a program with the default bootloader, save the file as main.py on the ESP board.

Getting Started with MicroPython on ESP8266