| Gentlemen,
I finally got my board into my Northstar Horizon for testing tonight.
I can confirm that I am seeing the same thing as described previously. RUN/STOP appears to operate correctly. RESET appears to operate correctly. Single Step appears to operate correctly. I think EXAMINE might be working (I can set an address, and EXAMINE and always get the same value).
I'm not so sure about EXAMINE NEXT - each press seems to cycle through 4 different addresses (non-sequential) then go back to the starting address.
DEPOSIT is definitely not working. I am unable to DEPOSIT a value into RAM.
My setup - Stock Northstar Horizon. The Northstar CPU board has a front panel connector which I have connected to the FP mini. Jumpers - all combinations have been attempted, and I'm unsure what the correct settings should be.
I can perform any debugging or testing if anyone can suggest what I should be looking for. Otherwise, I will wait for others to see what they find out.
Ian
Rich,
I'm having the same Examine problem with my board as well.
Josh had the last prototype working and all his mods went to the
schematic.
I need to go back and review our emails and make sure all the
changes got made.
On 03/ 1/15 03:05 PM, Richard Cini
wrote:
A quick follow-up. I did some probing of the LS123
one-shots and I discovered something interesting. Pin 12
(Q-prime) on both U17 and U20 are free-running. The other
one shots seem to be triggering properly. I don’t see any
immediate cause for this, so I swapped the chips but I get
the same result.
Rich
--
Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator
Guys —
I finished my
MiniFP board this morning and I can’t seem to deposit
to or read from memory using the EXAMINE toggle. The
“next” part of the function works, so I can step among
addresses but the data LEDs are all on all the time
(unless I set JP5 SSW_DSBL jumper). However, if I use
the SINGLE_STEP switch, the data bus LEDs appear to
reflect memory contents.
The experimental
system is very simple CompuPro RAM17 (64k), IMSAI 8080
board, and the front panel. Before I say that anything
is wrong, can someone confirm the jumpers? I think
only the MWRT should be jumpered. The RAM17 is an
IEEE-696 board so as I do for my IMSAI, I’ve isolated
pins 20/70 (UNPROT/PROT) on that board.
Chip-wise, I’ve
used LS (including the LS123 as recommended in the
Wiki) except the 7402. I don’t have any 7400’s
in-stock so I’m using LS00 for now…don’t know if
that’s part of the issue since those gates are used in
the EXAMINE circuit. I replaced the 8212 just in case,
but that had no effect. The data cable is fine.
Any help, even
questions to get me thinking, would be appreciated. I
feel I’m pretty close to a solution here.
Thanks!
Rich
--
Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator
--
You received this message because you are subscribed to the Google
Groups "N8VEM-S100" group.
To unsubscribe from this group and stop receiving emails from it,
send an email to n8vem-s100+...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
--
Don Caprio
ilv...@gmail.com
---
Filter service subscribers can train this email as spam or not-spam
here
--
You received this message because you are subscribed to the Google Groups "N8VEM-S100" group.
To unsubscribe from this group and stop receiving emails from it, send an email to n8vem-s100+...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
|