bcwik9 / Espruino-Apps

A collection of Espruino JS apps for the ESP8266 and ESP32 microcontrollers

Esrupino Apps for ESP8266 and ESP32

Variety of lightweight Espruino apps for a ESP8266 or ESP32 microcontroller.

General ESP8266 ESP12E Setup

Official flash tutorial

Tutorial found here

Pinout diagram here

• Flash your ESP8266 with Espruino firmware
  • I downloaded the "combined" file: espruino_2v01_esp8266_4mb_combined_4096.bin
  • Run command to flash on linux (I flashed using a raspberry pi):

    esptool.py --port /dev/ttyUSB0 erase_flash
    esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash --flash_size=detect -fm dio 0 espruino_2v01_esp8266_4mb_combined_4096.bin
    

    • Note: Your device could be on something other than /dev/ttyUSB0 depending on if you have other things plugged in, etc.
    • Note: You can use a higher baud rate (230400, 460800, etc) and the flash will be faster, but all devices don't support high baud rates.
    • This command worked for a ESP-01: esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash --flash_freq 40m --flash_mode qio --flash_size 4m 0x0000 "boot_v1.6.bin" 0x1000 espruino_esp8266_user1.bin 0x7C000 esp_init_data_default.bin 0x7E000 blank.bin
• You should now be able to connect to the ESP8266 by running: screen /dev/ttyUSB0 115200
  • To kill a screen session, press CTRL+a then k. A prompt should ask confirming you want to close, press y to confirm and exit
• Copy and paste the contents of whatever app js file to the ESP8266 terminal
  • This won't work if you are loading other modules besides Wifi since they need to be uploaded via the web UI
  • First be sure to replace your Wifi credentials in the file!
• (Optional) Run this command to set the name of your device to something recognizable in your router list and to other devices:

var wifi = require('Wifi');
wifi.setHostname("MyDeviceName");
wifi.save(); // load hostname even if power loss/restart

• Be careful of saving SSID/password with wifi.save(). It doesn't seem to work properly (has connection issue on reconnect/reboot?). Hostname seems to save and load correctly though.

Common Issues

• Not all USB cables support data transport (ie. some only supply power). If you can't connect try a couple different USB cables.
• The USB port you use must provide a good amount of power for a ESP chip to run successfully. Usually a common PC USB port will not provide enough power (and is not advised for anything except programming - you could burn your USB out). If you're having issues, try using a higher power USB port like a RaspberryPi provides.
  • It might appear that the ESP chip is working, but some things will not work until enough power is supplied (ie. you might be able to flash firmware, but not run/connect to Espruino via screen command). Certain functions like PWM or pin output might behave oddly.
  • I don't advise using the USB connection as a power source as a long term solution. USB ports tend to wear out and have unreliable connections once they have some wiggle/play in them. A better solution is to use the VIN pin to provide dedicated power (just make sure it's filtered to 3.3v or whatever it needs to be so as to not burn out the chip, if not using a dev board).

ESP12E non-development (NodeMCU, Wemos) setup

The bare ESP12E non-development board (ie. one without a micro usb connection and other chips built-in) requires some connections be made before it will start. After programming the chip (via a "frog" board or usb-to-uart serial adapter), make the following connections or the ESP12E won't boot correctly (it needs to be in the normal mode to boot from SPI Flash to run the code it was set up with). Note that some guides say you need to change GPIO2, but I don't think it's necessary.

ESP8266 Pin	Connection	Resistor	Notes
GND	GND	None
VCC	3.3v	None	Be sure to use filtered 3.3v source (a typical USB charger is 5v which will burn it out!)
EN (or CH_PD)	3.3v	None
GPIO15	GND	2k to 10k
GPIO0	3.3v	2k to 10k	Set to GND to enter UART bootload (programming mode)

If you want to utilize deep sleep, make sure you also connect GPIO16 to RESET (RST) to allow the ESP8266 to wakeup after sleeping. If you are not using deep sleep, you should connect RESET (RST) to 3.3v power (not sure this is necessary).

Sources:

• https://www.reddit.com/r/esp8266/comments/88dre0/do_you_need_a_resistor_when_pulling_chpd_en_up/
• https://www.hackster.io/brian-lough/3-simple-ways-of-programming-an-esp8266-12x-module-c514ee#toc-method-2--using-basically-any-usb-to-serial-converter-3
• https://www.instructables.com/id/Getting-Started-with-the-ESP8266-ESP-12/ (see step 3)
• https://www.instructables.com/ESP8266-Using-GPIO0-GPIO2-as-inputs/

Modules

Espruino Modules provide extended functionality for a variety of hardware and software services, such as One Wire interfaces, MQTT and database connections, WIFI functionality, graphical display interface libraries, and more. It's a good place for project ideas and sensors.

There are also instructions on how to write your own custom modules and load them straight from github.

Guides

• my eBay parts list
• Power Saving
  • Power Saving and batteries
  • Battery setup parts list guide
  • Use ESP8266/ESP32 deepSleep to save power (ie. require("ESP8266").deepSleep(micros, option))
    • note: ESP8266 and ESP32 each have different deepSleep functions/libraries
  • Solar powered temp sensor
    • Components
    • Algorithm
• recharge battery with solar power
• SIM800L
  • connection guide/pinout