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+# Converters
+
+Since many drop-in replacement controllers now exist, we've done our best to make them easy to use in existing designs.
+
+This page documents the handy automated process for converting keyboards.
+
+### Supported Converters
+
+Currently the following converters are available:
+
+| From       | To                |
+|------------|-------------------|
+| `promicro` | `proton_c`        |
+| `promicro` | `kb2040`          |
+| `promicro` | `promicro_rp2040` |
+
+See below for more in depth information on each converter.
+
+## Overview
+
+Each converter category is broken down by its declared `pin compatibility`.
+This ensures that only valid combinations are attempted.
+
+You can generate the firmware by appending `-e CONVERT_TO=<target>` to your compile/flash command. For example:
+
+```sh
+qmk flash -c -kb keebio/bdn9/rev1 -km default -e CONVERT_TO=proton_c
+```
+
+You can also add the same `CONVERT_TO=<target>` to your keymap's `rules.mk`, which will accomplish the same thing.
+
+?> If you get errors about `PORTB/DDRB`, etc not being defined, so you'll need to convert the keyboard's code to use the [GPIO Controls](gpio_control.md) that will work for both ARM and AVR. This shouldn't affect the AVR builds at all.
+
+### Conditional Configuration
+
+Once a converter is enabled, it exposes the `CONVERT_TO_<target_uppercase>` flag that you can use in your code with `#ifdef`s, For example:
+
+```c
+#ifdef CONVERT_TO_PROTON_C
+    // Proton C code
+#else
+    // Pro Micro code
+#endif
+```
+
+## Pro Micro
+
+If a board currently supported in QMK uses a [Pro Micro](https://www.sparkfun.com/products/12640) (or compatible board), the supported alternative controllers are:
+
+| Device                                                                 | Target            |
+|------------------------------------------------------------------------|-------------------|
+| [Proton C](https://qmk.fm/proton-c/)                                   | `proton_c`        |
+| [Adafruit KB2040](https://learn.adafruit.com/adafruit-kb2040)          | `kb2040`          |
+| [SparkFun Pro Micro - RP2040](https://www.sparkfun.com/products/18288) | `promicro_rp2040` |
+
+Converter summary:
+
+| Target            | Argument                        | `rules.mk`                   | Condition                           |
+|-------------------|---------------------------------|------------------------------|-------------------------------------|
+| `proton_c`        | `-e CONVERT_TO=proton_c`        | `CONVERT_TO=proton_c`        | `#ifdef CONVERT_TO_PROTON_C`        |
+| `kb2040`          | `-e CONVERT_TO=kb2040`          | `CONVERT_TO=kb2040`          | `#ifdef CONVERT_TO_KB2040`          |
+| `promicro_rp2040` | `-e CONVERT_TO=promicro_rp2040` | `CONVERT_TO=promicro_rp2040` | `#ifdef CONVERT_TO_PROMICRO_RP2040` |
+
+### Proton C :id=proton_c
+
+The Proton C only has one on-board LED (C13), and by default, the TXLED (D5) is mapped to it. If you want the RXLED (B0) mapped to it instead, add this like to your `config.h`:
+
+```c
+#define CONVERT_TO_PROTON_C_RXLED
+```
+
+The following defaults are based on what has been implemented for STM32 boards.
+
+| Feature                                      | Notes                                                                                                            |
+|----------------------------------------------|------------------------------------------------------------------------------------------------------------------|
+| [Audio](feature_audio.md)                    | Enabled                                                                                                          |
+| [RGB Lighting](feature_rgblight.md)          | Disabled                                                                                                         |
+| [Backlight](feature_backlight.md)            | Forces [task driven PWM](feature_backlight.md#software-pwm-driver) until ARM can provide automatic configuration |
+| USB Host (e.g. USB-USB converter)            | Not supported (USB host code is AVR specific and is not currently supported on ARM)                              |
+| [Split keyboards](feature_split_keyboard.md) | Partial - heavily dependent on enabled features                                                                  |
+
+### Adafruit KB2040 :id=kb2040
+
+The following defaults are based on what has been implemented for [RP2040](platformdev_rp2040.md) boards.
+
+| Feature                                      | Notes                                                                                                            |
+|----------------------------------------------|------------------------------------------------------------------------------------------------------------------|
+| [RGB Lighting](feature_rgblight.md)          | Enabled via `PIO` vendor driver                                                                                  |
+| [Backlight](feature_backlight.md)            | Forces [task driven PWM](feature_backlight.md#software-pwm-driver) until ARM can provide automatic configuration |
+| USB Host (e.g. USB-USB converter)            | Not supported (USB host code is AVR specific and is not currently supported on ARM)                              |
+| [Split keyboards](feature_split_keyboard.md) | Partial via `PIO` vendor driver - heavily dependent on enabled features                                          |
+
+### SparkFun Pro Micro - RP2040 :id=promicro_rp2040
+
+Currently identical to  [Adafruit KB2040](#kb2040).