ELM11-Feather is a new, unique microcontroller board that is natively programmable in Lua. It aims to complement the current offering of Feather-compatible, scriptable microcontroller boards.

The current ecosystem of natively scriptable microcontroller boards are programmable in Python. Unlike Python, Lua was specifically designed to be fast, efficient, and lightweight, making it a fantastic scripting language for embedded systems. Other boards can be modified to gain Lua compatibility, but native support gives users far tighter hardware and software integration.

Lua Your Life

Applications encompass any and all projects that are currently possible with existing scriptable microcontrollers with similar hardware specifications. Its Feather compatibility allows the board to be used with any of the available Featherwing PCBs. Those that are fans of both embedded system development and the Lua scripting language will find the board a natural fit for their projects, especially those with need for a lot of I/O.

Of course, the ability of the user to compile their own, custom, ‘hardware overlay’ is a boon, extending its usefulness. This can let creators tailor the hardware to their specific use case. Moreover, the firmware API will also be released, making development of custom hardware modules and expose their functionality to the scripting layer possible. For example, the user could develop a custom quadrature encoding hardware module, build it into the hardware overlay, and then define Lua functions such as quadrature_encoder_direction, quadrature_encoder_speed, and others.

Features & Specifications

Hardware

• Compatible with the Feather specification. (Note that the specification does not require analog pins. In our case the six reserved spots that may be analog pins are digital I/O pins.)
• CPU clocked at 70 MHz (default hardware overlay)
• 1 MB RAM
• Hardware Watchdog
• 3.3 V regulator with 500 mA peak current output
• 20 I/O pins, each supporting:
  • GPIO
  • PWM
  • UART
  • SPI
  • I²C
• 5 user-programmable LEDs
• User pushbutton
• Reset pushbutton
• 4 mounting holes
• Built in 500 mA LiPoly charger with charging status indicator LED
• Dimensions: 22.86 x 64.65 x 4.85 mm (0.9 x 2.54 x 0.191 in)
• Weight: 7.3 g (0.26 oz)

Firmware

• Executes Lua, from either:
  • REPL (There a standalone REPL for each CPU core)
  • Program(s) stored on the Flash
• Support for standard digital I/O protocols, including GPIO, PWM, UART, SPI, and I²C
• Interrupts, including UART, SPI and I²C receive data
• Timers
• Hardware-based watchdog
• Run-time reconfigurable hardware (I/O type, frequency, boot configuration, etc.)

Open Source

ELM11-Feather is designed to be open, because we hope that a community will form around the board and users will contribute and share their customizations. We will make hardware schematics available under the MIT license. Our firmware API will also be open source under the MIT license. All of this information will be made publicly available during production of the board, after the crowdfunding campaign closes.

Right now you can access plenty of documentation available for the original ELM11, including the datasheet, online docs, schematic, and example programs.

Interested in This Project?

You can sign up at the top of this page to be notified when the campaign launches and to receive other updates. We only send out relevant content, and you can unsubscribe at any time.