Features

• Bluetooth Low Energy
• Espruino JavaScript interpreter pre-installed
• nRF52832 SoC - 64MHz ARM Cortex M4, 64kB RAM, 512kB Flash
• Sunlight readable monochrome display with white backlight
• 20 x GPIO in Arduino footprint (capable of PWM, SPI, I2C, UART, Analog Input)
• Support for GSM, LTE, WiFi and Ethernet Arduino shields
• 2.5v to 16v input range (0.3mA idle)
• CR2032 battery holder (Battery not included), or Micro USB (power only)
• 4 x 3mm mounting holes
• 4 x buttons
• Built in thermometer and battery level sensors
• NFC tag programmable from JavaScript
• Dimensions: 60mm x 53mm x 15mm (2.4 x 2.1 x 0.6 inches)

Powering Pixl.js

Pixl.js can be powered in multiple ways:

• Micro USB - the Micro USB connector can easily provide power to your Pixl.js (there is no data connection)
• CR2032 Lithium battery - a CR2032 battery will power Pixl.js for around 20 days with light JavaScript usage. Battery not included
• Vin pins - available via the Arduino header, or the separate pin header to the side. You can supply 3v - 16v which is regulated down to 3.3v for Pixl.js. The unpopulated pins to the side are spaces to accommodate a connector for JST PHR-2 Batteries.
• CR2032 LiPo battery - you can not use a CR2032 LiPo battery without some minor modifications as the voltage is too high. There is a small solder jumper below the CR2032 holder. Cut the existing connection and solder between the other two pads. This causes the battery to be connected via the voltage regulator. Note: the LiPo will then be connected directly to Vin, and you will be unable to use the USB for power (as it'll connect to LiPo to 5v).
• CR2032 battery backup - the CR2032 can be used as a backup when Vin/USB power is not present. Cut the trace in the solder jumper below the CR2032 holder, and add a surface mount diode to the two pads to the right of it.

While the main advantage of the Espruino is its instant execution, it can also be used as a traditional board through a Web-based IDE hosted on your computer. The microcontroller also uses less power than Linux Boards (although its of course a lot less powerful as well) so will run longer on battery power. There's also much more info on the Espruino Pixl.js page including tutorials, code examples, manuals, datasheets, and more!

For other great embedded Javascript development boards from Espruino, check out the classic Espruino and the little Espruino Pico.