Originally Posted by paulsm4
Frankly, you probably don't have to do much of anything besides:
a) Figure out the right device interface (e.g. "/dev/ttyUSB")
b) Read and write to it (just as you'd do I/O with any normal file)
However - if you want some Deep Background - this looks like a good tutorial:
'Hope that helps .. PSM
Wow, I wonder if that's all there is to it... I'll give that a try and report back here. Won't be for a while though.
There are other complications to this project. For one thing it requires almost real-time performance. (The "almost" means there is an allowable time slice of delay).
The Gentoo is actually a Gentoo/RTAI real-time OS. I have no idea what exactly the functional difference between a real-time OS and a regular OS is, will need to bone up on this as well.
There is also the fact that this is a very minimally-compiled Gentoo, such that automatic USB polling is turned off. So we won't know which of the USB ports in the PC the cable was plugged into. However it is acceptable to the client to have the operator enter some command specifying this at start time. But I'll still need to learn about how the different USB ports on the machine are accessed and referenced.
Thanks for the reply and the link, paulsm4.