Anybody know any hardware for I/O that works on Linux? I use the FTDI line of chips, but I often feel like I am reverse-engineering what is supposedly open-source hardware. I've contributed a bit to libftdi. I am interested in digital I/O that is USB based, since that seems to be where the world is going. The old standard parallel port is out, since you can no longer depend on them being on new computers and the USB ones are not true parallel ports in the classic sense of the word. I am of course interested in both digital and analog I/O, which is possible with the FTDI chips. There is a Tolken I/O protocol that supposedly interacts with a PIC processor to obtain analog and digital I/O using the FT245 in FIFO mode. Another possibility is DataQ. Their DI-194rs is supported on Linux. It is a 4 port A/D with +/- 10V, 0-20V, and 0-5V input, 10 bits, and max 256 S/s. The sample rate is pretty slow, but good for sensors reading low-speed conditions like temp, wind velocity, humidity, etc. Cheers!