Tag Archives: Arduino

Recovering Arduino Pro Micro Atmega32u4

I was doing something with foolish in avrdude, ending in me killing the bootloader on my Arduino Pro Micro . The Arduino Pro Micro bootloader creates a USB connection which the user can upload code, however by overwriting the bootloader, the chip no longer enumerates as a USB device and can no longer accept new sketches. Fortunately, I hadn’t messed up the fuse bits, so I can still upload using ISP. There wasn’t much documentation on doing this for a Pro Micro, so I had to look up the data sheets for the chip and trace the Eagle PCB schematics. Fortunately, all of the ISP connections are accessible via the pin headers. I used my USBasp, but any ISP programmer including another Arduino running Arduino ISP should work. Read more »

Grbl CNC USB to TB6560 Interface using Arduino

I’ve had a CNC mill for a few years now, and while many homemade CNC mills use EasyDriver or Pololu, mine came with a sturdy, generic TB6560 controller board. For those unfamiliar, boards like this are interfaced using an old fashioned LPT parallel port, which was initially an annoyance, but quickly became impractical and a hassle, having to use an old PC with VNC installed. The board has plenty of power to push the steppers around, far more than any of the smaller / cheaper solutions had to offer I think, so I wanted to try and teach this board a few new tricks, and let me interface with it using a more modern interface. Read more »