roy@phri.UUCP (Roy Smith) (05/24/85)
I am looking for a system to interface with equipment in a research lab. The idea is to have a toolkit so I can quickly throw together the stuff to control (as of yet unplanned) experimental setups. The easy but expensive way would be to go the IEEE-488 route, but for what I have in mind, that may be overkill. I will want to accept low-level electrical inputs (V, I, and R) from thermocouples, photodetectors, pH meters, and such, and be able to control pumps, heaters, coolers, etc. Undoubtedly, analog output (V and I) will be needed in addition to power-line relays. Analog precision of 8-12 bits will probably be enough, but 16-bit might be occasionally useful. Signal conditioning (log amps, diff amps, etc.) will be required occasionally. I/O rates probably don't have to be much above a few kHz, if that. At least 16-bits of TTL input and output will probably be required. One RS-232 line is essential (to get the data back to our Vax); more would be nice. IEEE-488 capability might be useful, but is not required. I envision a box that hangs off a micro, so these requirements would probably be met by that. We won't need too much in terms of processing power, so Apple-II based systems are probably OK. I have no real fear about doing my own low-level programming when required, but having access to the devices from BASIC (or, dare I say it?, from C) would be real handy for quick setups. -- allegra!phri!roy (Roy Smith) System Administrator, Public Health Research Institute