Re: [Emc-users] usb parallel port possible?

[Jeff E. <je...@un...>]

When emc uses a parallel port to send "step and direction" signals to a
stepper motor driver, the signals must be received by the driver at
precise intervals measured in microseconds.  This is perfectly possible
with most built-in or PCI-slot parallel ports, but it is simply not
possible with a USB parallel port.

On the other hand, if you wish to control things that work at a long
timescale, like relays, it would be possible.  Personally, I would
recommend writing a "userspace" (as opposed to realtime) driver, because
then you can use the normal Linux kernel drivers for USB devices.

Jeff