ggr (11/12/82)
I am trying to use an INTEL 8274 Multi-Protocol Serial Controller (MPSC) chip in HDLC mode and have not been very successful at programming it based upon the information contained in INTEL's spec sheet. The only way I have gotten the chip to do anything was by starting with a program that seemed to follow the rules (or suggestions) in the official specs, which gave a program that didn't work at all, then by making almost random permutations, keeping those that seemed to make things better. Folklore and assorted hints from other designers also contributed. Well, now I have a program that works pretty well *most* of the time with *one* 8274 chip. But it seems there are different versions of the chip out in the world and a program that works with one version won't with another (and unfortunately when we purchase chips, we seem to get assorted versions). So what I would like to do is write a program that would work with all (or at least most) versions. Two requests: 1. Does anyone have a list of all the different versions of 8274s made and what is different about them? 2. Do you have any hints on how to make 8274s work (any mode) -- corrections to what the manual says or additional procedures, sample programs (just the I/O portions), etc.? I'll summarize any responses I get and post them back. Thanks, as they say, in advance. === Guy Riddle == BTL Piscataway ===