First post, by dionb
- Rank
- l33t++
Several months ago I was buying a motherboard from someone and he offered to chuck something ancient he couldn't figure out in the deal. That something turned out to be a Wyse PC386 SBC-type motherboard with daughterboard and one connected memory board, all designed to be plugged into a 16b ISA backplane.
At the time I didn't have a backplane nor did I have a CPU or keyboard with Wyse RJ11 connector. But bit by bit I got the necessary pieces until I was at last ready to test it. First test was a complete zero, not helped by an untested CPU. But this evening I got my hands on another supposedly known-good CPU and got to work again. At first it was as unsuccessful as before, but one time I suddenly saw "02" on my POST card. There was some life left in it. So I redoubled my efforts. I checked all the jumpers (surprisingly few given its age and complexity), but everything was set correctly. I removed and re-mounted all the socketed chips (lots of them...) and still nothing more than that "02" if I was lucky. If not it was "00" or "01".
Finally I tried to figure out what the "02" meant. A quick google showed that the Wyse BIOS was a rebranded Phoenix BIOS - but not which one. So the 02 was ambiguous. Then I figured that it might be beeping at me so I got a speaker and tried that. Supposedly J4 ("Power good/Speaker ") was the one for that. The only way you could fit a standard 4 pin, 2 wire speaker cable didn't do anything, so I tried other combinations. Still no beeps, but suddenly one boot attempt the POST card shot through to 27. So I fiddled some more and discovered two combinations of pins that reliably gave me 27 and very, very rarely (twice to date) actually booted fully. That means I now know it's a Phoenix 80386 ROM BIOS Version 3.52 and that the 02 and 27 were probably CMOS read error and keyboard controller failure. Note that the system responds to keyboard when it boots.
So, IT's ALIVE!
However behaviour is still extremely flaky, no doubt because I'm (ab)using a speaker to do something that should be related to "Power good". So my question is if anyone knows what these pins are expecting so I can provide that instead.
This is the motherboard:
http://stason.org/TULARC/pc/motherboards/W/WY … MODEL-3216.html
The pins are at J4 on the daughterboard.
It looks like this:
o o o . o
1 2 3 4 5
(possibly I have the numbering the wrong way round, there's no clear pin 1)
If I connect either 1 or 3 to 5 I get at least a 27 and maybe a boot. I'm a bit reticent about just shorting 3 to 5, out of fear of damaging something that expects some resistance.
