Matthew Sullivan wrote:
MicroPose (MicroProse?) - do the Micro2000, which is a rather useful POST probe.....
It's not cheap, but well worth it for the usefulness, it is listening address configurable, and will provide extra diagnostics like Osc check, clock check tri state logic probe, and of course all the voltages....
We *could* make our own. A POST card is an ultra-simple device, It simply latches data from a specific port reserved for POST (I forget which one off-hand though) and displays it via either a bank of 8 LEDs in binary or two 7-segment LED displays in hex.
There are schematics in many electronic magazines (when Microcomputer Journal was Computercraft, I believe they ran one, I think Popular Electronics also ran one a while ago). I can search through all of my old magazines to find the basic schematic.
We can add extra features as we wish, for example, a PIC could be thrown on there to translate the data to a serial port (on the card, of course) or to an LCD module with extra information. It doesn't matter that the PIC is slower than the PC.
We could also add extra functionality such as a simple parallel i/o port, i2c (which the PIC could handle nicely), analog switches, etc. We could set it up to display POST codes on an LCD or LED module on the front of the PC (it gets hard to read the display on a POST card if other cards are blocking it).
We could even build a ROM programmer into it as an external module.
This is an easy design, even with all the extra features. I have an ISA prototype card I can play with.
The most expensive part would be, of course, the PCB (I paid CAN$50 for my prototype card) but if a bunch of us wanted to make some (I have many friends who would be interested in such a device, parallel ports tend to run out quickly) we could get away with some relatively cheap PCBs if we find the right place (I hear ExpressPCB is pretty cheap).
If anyone's interested (we *will* need post cards, especially for debugging purposes), respond. It would also be nice to have a ROM burner on it as I'm sure we will all need one of those as well.
James Oakley jfunk@roadrunner.nf.net