cahalan@iris613.gsfc.nasa.gov (Bob Cahalan) (07/10/90)
The simplest method of getting data into the PC that I know of is illustrated in a paper appearing in the upcoming (July/August) issue of Computers in Physics, entitled "Chaotic Rhythms of a Dripping Faucet", by myself and a colleague here at Goddard, and my son (who actually did all the work). The C program given there shows how to determine the time intervals between the rising edges of 5V pulses input to pin 11 of a PC parallel port. To get accuracies better 55 ms (the BIOS clock), data must be accumulated in memory, and only written to disk after returning to the default timing. If memory is sufficient to do that, accuracies much better than a millisecond are attainable. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Robert F. Cahalan # Laboratory for Atmospheres cahalan@iris613.gsfc.nasa.gov # NASA-Goddard Space Flight Center frrfc@scfvm (bitnet) # Greenbelt, MD 20771