programmable digital I/O.. what should I buy?



Hi Everyone,

I want to make a programmable digital I/O device to coordinate some
experiments I'm performing. I'm not sure what to buy, please help me
out.


Here's what I need:
at least 8 channels of digital I/O
timing resolution of 10 microseconds or better
on-the-fly digital output changes based on digital input (easily
re-programmable via computer)

For example,
when channel 2 goes high, less than 10 microseconds later, five 100
microsecond long pulses at 100 Hz are generated on channel 4.


Since my timing requirements are so tight, I can't run it off of
windows to change the outputs based on the inputs. I've been told that
an RTOS (real-time operating system) running on a microcontroller is
overkill. I only want to make one of these, but I'll use it a lot. I
can program in C++ just fine and would like a device that comes with
some software to make it easy to program. Ideally, this would be a
USB-attached device, but I'd be interested in PCI board solutions as
well.

So what should I buy?

Thanks in advance,
-james

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