3.3v regulator, DFU bootloader, firmware, STM32F042
pcb robot

Red Hot PCB: OpenMV Anniversary Gift

This week’s Red Hot PCB comes from OpenMV and is a anniversary gift for his wife. This MiniMe uses an STM32F042, because it is a “crystal-less” USB MCU (meaning it supports USB without needing crystal) so less parts to worry about. Also this MCU has a built-in DFU bootloader which runs if there’s no firmware. The first time the board is connected it shows up as a DFU device which allows uploading firmware. If the firmware needs to be updated again, the bootloader pins can be shorted to re-run the bootloader (basically, you just short the toes :)) . The PCB edge is also used as a USB connector, so it can be plugged to a USB port directly.


Finally there’s an RGB LED connected to PWMs, no other major parts, some passives and a 3.3v regulator. This sweet device uses the PWM to modulate the RED LED in a breathing or pattern. This is going to be an anniversary to remember!


Did you like this post or find it helpful in any way? Let us know in the comments below!