ST Link v2 clone as a dev board

I got distracted and had a hack on using a STL Link v2 clone as a development board. There’s a lot to like:

• A Cortex-M3 STM32F103C8T processor with 64 KiB of flash and 20 KiB of RAM
• 4 I/O lines and a LED to blink
• Decent support in STM32duino with a DFU bootloader
• Comes in a case and plugs directly into a USB port
• ~$2/each

The I/O is strange and limited but it’s enough to drive a RGB LED via PWM, drive a 40 RGB LED pHAT over SPI, and drive a 320x240 LCD over fast bitbanged SPI.

I won’t continue with this though. The I/O is too limited and a Blue Pill is the same price sans case.