Skip to content

user_guide_en.md

Latest commit

 

History

History
57 lines (31 loc) · 3.21 KB

user_guide_en.md

File metadata and controls

57 lines (31 loc) · 3.21 KB
Raw

BIT-C

Pro Micro Compatible MCU with USB-C

User Guide

Contents

Helpful Links
Burning the Caterina (Arduino) Bootloader
Building for a Bit-C without flashing a new bootloader

Helpful links

Burning the Caterina (Arduino) bootloader

The Arduino IDE does not support programming the ATmega32U4 via the DFU bootloader, which is the default bootloader on the Bit-C. Fear not, though! Flashing the Caterina bootloader allows the Bit-C to be programmed directly from the Arduino IDE. This process is relatively straightforward and can be done directly from the Arduino IDE.

Note: this can also be done over the command line, e.g. for Linux users, or using a Raspberry Pi instead of an Arduino, but those are more advanced and won't be covered here directly. Hit up the Googles or pop into our Discord server and ask if you're wondering about these or have a different setup.

You'll need:

  • A USB Arduino (Pro Micro, Uno, etc)
  • The Arduino IDE, with the Sparkfun AVR board definitions installed

Steps:

  1. Configure the Arduino as an ISP

    An Arduino can be used an an “ISP programmer”. It’s a clever way of reusing an arduino instead of needing to buy or get ahold of a dedicated programmer.

    Sparkfun has a great tutorial on this. It’s a bit wordy, so don’t feel like you need to read the whole thing. The most important part is the one titled “Option 2: Using the Arduino as a Programmer”.

  2. Hook the Arduino up to the Bit-C

    The programming pins on the Bit-C are the same as a normal pro micro. Use this link for reference.

  3. Burn the bootloader

    Make sure to select the Sparkfun Pro Micro with ATmega32U4 (5V, 16MHz). Then, use Arduino IDE to burn the bootloader.

Building for a Bit-C without flashing a new bootloader

It's also possible to build an Arduino sketch and then flash with QMK toolbox. The benefit of this is that the Bit-C doesn't need to be flashed with a new bootloader. Beware, though: complex code might not work as expected when using this method.

The below example shows how to compile a sketch within Arduino, and then flash using QMK Toolbox. It will blink the Bit-C LED at all 3 brightness levels @ 1Hz. The benefit of this is that you don't need to burn the Caterina bootloader.

Compile this with Arduino IDE for a 5V (16MHz) Pro Micro, and then export by choosing 'Sketch --> Export compiled Binary'

Point QMK toolbox to 'test.ino.promicro.hex' (the one WITHOUT the bootloader), reset the Bit-C into the DFU/bootloader mode, and flash.

https://gist.github.com/jaygreco/d82c83a441d5953b4c98d5e1aaebc104