Date : Fri, 12 Jan 1990 06:08:49 GMT
From : rzh@lll-lcc.llnl.gov (Roger Hanscom)
Subject: S-100 Cromemco 8PIO ... help?
Does anybody have dox for an S-100 Cromemco 8PIO, or know anything about one?
I have a bunch of questions about the board. I bought it for scrap, and of
course there was no documentation with it at all.
/-------------------------------------------------------\
| xxxxxxxx ------- ------- ------- ------- ----- |
| | H67 | | H45 | | H23 | | H01 | | R | |
| ---------- ------- ------- ------- ------- | 1 | |
| | S1 | C R O M E M C O 8 P I O ----- |
| ---------- ----- |
| ---------- | R | |
| | S2 | | 2 | |
| ---------- ----- |
| |
| |
| |
| |
| |
\_____ ------------/
| |
----------------------------------------
1. S1 & S2 are 8 position dip switches. The leftmost 5 bits of S2 set the MSB
of the card address (A3->A7), and then the 25-pin headers (H0->H7) are the
8 parallel ports counting up from the base address. What are the rightmost
3 positions of this switch used for?? They are marked D0->D2.
2. The x's represent 8 LEDs that seem to be controlled by the 8 bits of S1,
and seem to appear on port7. Surely there must be more?? What am I
missing??
3. Each 25-pin header (Hkl) has the following pin-out:
? 0 1 2 3 4 5 6 7 ? ? ? * <---port l
? ? ? 0 1 2 3 4 5 6 7 ? ? <---port k
where pin * is cut off. I can find the bit positions (as shown), and the
?'s are probably handshakes, etc. But which are what? R1 and R2 are
relays, and R1 audibly latches on pins 0 and 1 of port 1. What are they
used for and how?
4. To the left of the relays there are jumper positions marked: NC, Jn-24,
Jn-23, and PIC, where n is 4 for R1 and 3 for R2. What are these for?
Jn-23 and Jn-24 are connected to pins 23 and 24 of H01 and H23. Do bits
0 and 1 of ports 1 and 3 supply AC or DC to pins 23 and 24 of the header?
The relays are marked: "*SIGMA (* is a backward RU)
60RE1S-5DC
1A,28VDC
.5A,120VAC"
The board has an optoisolator on it MCT66, and one other jumper (factory
installed??) labeled "Port 6 out". It is: REV. E1, MOD LEVEL 1.
The card is in really good shape, and is quite usable, as long as I can get
some help on these questions. I will appreciate any clues.
roger rzh@lll-lcc.llnl.gov