ESP8266 References and Notes

Checklist for boot fails:

• write_flash succeeds but the program doesn't run

Some References:

• Good Pin Information
  • Pin information for Huzzah
  • Schematic for Huzzah
• ESP8266 Hardware Design Guideline
  • GPIO Maximum current I-max
    • Typical output current 6mA (info source origin unknown)
    • Maximum output (source) current from one GPIO pin is 12mA
    • Maximum sink current about 20mA
  • The 12mA is the maximum amount of current you can safely pull from the ESP32 - While this is about the ESP32. it has good information about how to think about maximum drive strength vs. current.
• ESP8266EX Datasheet - seems to be missing AC Characteristics of the GPIO pins. ☹️
  • Here is a very old datasheet with potentially incorrect info. It has some info I cannot find in the current datasheet. ☹️
• ESP8266 SDK Getting Started Guide Version 3.1
• ESP8266 Non-OS SDK API Reference Version 3.0
• ESP8266 Reset Causes and Common Fatal Exception Causes
• ESP8266 SDK Application Note Firmware Download Protocol
  • Among other things, it has the Firmware Image Format.
• Expressif's ESP8266 Documents
• esp-open-sdk
• GPIO Pin tricks for driving multiple LEDs
• GPIO Pin tricks Charlieplexing for driving multiple LEDs. 4 pins to drive 12 LEDs
• ESP8266 pinout reference and how to use GPIO pins good overview

Pointers to lwIP stuff:

• lwIP wiki
• m-lab lwIP
• m-labs/lwip/doc
• Self documentation of the source code, extracted from Git sources.
• esp82xx-nonos-linklayer
  • Instructions for building

Interesting Arduino ESP8266 Projects:

• fauxmoESP (Alexa support via Philips Hue)