ESP

ESP8266

• http://l0l.org.uk/2014/12/esp8266-modules-hardware-guide-gotta-catch-em-all/
• http://www.esp8266.com/wiki/doku.php?id=esp8266_gpio_pin_allocations
• ESPtool with pre-build binaries https://git.48.io/esptool
• Luatool fork https://github.com/hackerspace/luatool

Flashing NodeMCU

• Clone ESPtool from https://git.48.io/esptool

<syntaxhighlight lang="bash">git clone https://git.48.io/esptool.git</syntaxhighlight>

• add jumper to flash enable pins - isolated pin header with two pins GPIO0 and GND.
• connect VCC and GND pins to 5V on USB serial converter
• connect ESP RX/TX pins
• try plugging in serial converter, led on the ESP should blink briefly
• flash dev firmware (or debug firmware if needed)

<syntaxhighlight lang="bash">cd esptool ./flash_bin_dev</syntaxhighlight>

• remove jumper
• start terminal with 115200 baudrate

<syntaxhighlight lang="bash">miniterm.py /dev/ttyUSB0 115200</syntaxhighlight>

• disconnect and re-connect power to ESP (preferably without disconnecting USB serial converter as you wouldn't see early boot messages)
• NodeMCU should start
  • during first boot you should see Self adjusting flash size and Formatting filesystem messages
  • after formatting you should get NodeMCU prompt >

<syntaxhighlight lang="bash">Early boot

$ miniterm.py /dev/ttyUSB0 74880

Program

$ miniterm.py /dev/ttyUSB0 115200

sometimes

$ miniterm.py /dev/ttyUSB0 9600

Flashing custom build nodemcu

./esptool.py -b 921600 write_flash -fm dio 0x00000 bin/0x00000.bin 0x10000 bin/0x10000.bin

NodeMCU build

customization

app/include/user_config.h app/include/user_modules.h app/include/user_version.h</syntaxhighlight>

<syntaxhighlight lang="bash">triac_reg_pinout

0: GPIO16 1: GPIO5 230 sense 2: GPIO4 triac out 3: GPIO0 (Special: Bootloader when low) 4: GPIO2 5: GPIO14 debug led 6: GPIO12 ws2812 4x4 array 7: GPIO13 8: GPIO15 RX: GPIO3 TX: GPIO1 A0:</syntaxhighlight>

<syntaxhighlight lang="bash">toggle(dir_pin)

slider_pinout

0: GPIO16 1: GPIO5 enable 2: GPIO4 direction 3: GPIO0 (Special: Bootloader when low) 4: GPIO2 debug led 5: GPIO14 step 6: GPIO12 ws2812 4x4 array 7: GPIO13 8: GPIO15 RX: GPIO3 TX: GPIO1 A0:</syntaxhighlight>