Not long ago, the PIC microcontroller was the go-to choice for rapid prototype development. However, their mix of features and low cost gave way to the Arduino ecosystem. Being pin-compatible with the Uno's form factor is a defining characteristic of an Arduino-compatible board. Capitalizing on the PIC18F's capabilities and the Uno form factor's popularity, MH-EDU-Electronics developed an exceptionally flexible Uno-compatible PIC development board called PICDEV USB.
PICDEV USB's physical shape follows the same outline as the Arduino Uno. The pin headers have the same space and (mostly) follow the Uno pin functions. However, if you carefully scrutinize the board, you may notice something is missing from the development kit. There is no microprocessor chip!
This devkit supports 20-, 28-, and 40-pin through-hole variants of the Microchip PIC18F family. The board only supports one of these chips at a time, but you can choose whichever fits your application best. Not only that, but it provides additional flexibility.
For example, there is an on-board 12 MHz crystal oscillator. But you can also add a second oscillator and select between the two via jumper. Another jumper lets you choose between USB or external power to supply the 5 volt rail. Unlike Arduino boards, there is no voltage regulator for voltages above 5 volts.
Another choice available to you is a USB Type-C or Type-A connector. Since the PIC18F has native USB support, there is no need for an additional chip to provide the USB-to-Serial interface, like on the Uno.
There are a few differences from the Uno form factor. For example, one difference already mentioned is the lack of an on-board regulator. Another difference is the ICSP header is on an edge. This placement means there is no six-pin header around the middle of the board. Some shields use this header to access SPI signals.
Despite those minor differences, PICDEV USB opens up the PIC18F family to the Arduino-compatible shield ecosystem.
The price for a PICDEV USB starts at $19.99 before shipping. You can change the USB port and have the board ship with a PIC microcontroller for an extra charge. For more information, check out the PICDEV USB product page on Tindie.