f89ba@rigel.efd.lth.se (07/16/90)
I have a 12 MHz AT-clone with a SUNTAC chipset. The documentation
is rather poor, and I need to know to things:
* What clock frequency the 80287 uses (I plan to install one,
but don't know what frequency it runs at)
* What clock frequency the bus is running at (probably 6 or 8 MHz)
I realize that the only way to get this info. is to measure the
frequency. I have access to the neccessary instrument (a counter),
but I'm not sure if it's safe to connect it to the signal lines
mentioned above. The counter's input is rated as 1 MOhm in parallel
with 25 pF, which would mean an impedance of 600 Ohm at 10 Mhz.
Should I use some sort of buffer between the signals and the counter?
What would this circuitry look like?
I would like as many details as possible, because I'd hate to
damage some part of my computer.
Thanks in advance
Bengt Ask, Lund Institute of Technology, Lund, Sweden