I started working on the 3D printed 6-axis robot arm shown below, but I needed a stepper controller that would: 1) support coordinated motion of at least 6 axes, and 2) be small enough to distribute inside the arm structure to minimize the wiring headaches. The Tic T500 is an ideal size, but it doesn’t support coordinated motion. So wrote my own alternate firmware for the on-board PIC18F25K50 processor. It uses a path point buffer that allows the host (in my case, a PC) to load multiple controllers with path data and then simultaneously start the motion of all motors. Here’s a link to a folder containing the firmware source code and HEX file, source code and executable for a Windows test utility program, and a PDF document describing how the firmware works: TicStep Files
Note that this involves programming the PIC18F processor directly, overwriting the standard Tic firmware (including the bootloader) – there is no turning back! You’ll need a PIC in-circuit programmer (like the PicKit 4) to program this new firmware. Please note also that Pololu does not support this firmware (although I’m happy to answer questions), and using it will undoubtedly void any warranty. As for my part, I offer no warranties either - use at your own risk. Please let me know what you think!
And here is a screen shot of the Windows test utility for testing the firmware on multiple controllers: