Wednesday, November 25, 2009


I started another FreeJALduino project - "USB-CDC - XYZ CNC Router board": a 3 axis CNC Router on USB. I'm using JALv2 compiler with Jallib libraries and frejalduino.jal, a layer between Arduino language and JAL language. As for USB communications, it use USB Serial library made by Albert Faber for sending/receiving signals to/from PC. I made a testing montage and a testing program.

The final target is a functional shield for FreeJALduino board which permits direct connections of three steppers, a limit switch and three LED's as indicators. A PC host program will parse gcodes and will send strings to the board, something like here:


Is my first trial. If it will fail to work as expected, I will try USB HID approach...will see...


  1. Hi Vasi, think that USB-CDC should work better because the bit rate ia 12 MBit, while HID devices are limited to 1.5 MBit. The fastest way is just to just raw packets (as for example is done in the bootloaders), however, they do require some effort on the host side. Albert

  2. Thank you Albert, I made some tests and I'm pleased by the results regarding to speed.