Electrical and physical to ease interconnecting both TU55 and TU56 to a TD8E. The TU55 have the G888 or G882 in the controller while the TU56 can have them in the drive or in the controller. When using Anders new set of cards both type of drives can be used with TD8E.
For USB interfacing I then thought it could be useful to do a small device the integrate a small CPLD that deals with the realtime stuff equivalent of what the TD8E is doing and a STM32 blue pill for USB interfacing. This board would then have a TD8E compatible interface for ease of integration with Anders boards or a TU56 with G888s in it.
Done some preliminary stuff in VHDL. But not finished yet:
https://github.com/MattisLind/td8e_usb