USB IO module

I saw that also and I have 3 of those boards, they are decent boards.
my concern with this is he's looking to sell these. my hope is he's designing his own board and not using this on. basically, relying on someone else who could stop production at anytime is usually not a good thing.

I wish him luck and it appears to work well.

I've played with the teensy code and find it ok but has some quirks and of course you have to add your own relays and input protection to teensy.

Seen a post on the zone looks like he shelved the project due to MCU change on the board.

Yeh, that's why you don't based offerings on other hardware, you have no control.
and one of these type of boards is not that hard to design.

There has been a little progress on this board, new version with Pro Mini and this: www.dhgate.com/product/dc-5v-12v-24v-4-c...board/392767641.html daughter board.

There is a free version that supports one I/O.
jsea.tech.blog/arduino-uno-pathpilot-usb-i-o/

Github:
github.com/jwatte/teensy_tormach_usbio

Hope this helps.