I assembled Dwight Elvey's KIM-1 debug board (thank you, Gary!) and have now
certified two of my KIMs with it, so I'm very confident the harness operates
properly.
Unfortunately, the one I *want* to repair, my original KIM-1, won't start up at
all after replacing the 2102 RAM I was pretty sure was bad. I checked my
soldering and found a couple spots without continuity that should according to
the schematic, but fixing those didn't fix it. I also buzzed out the socket and
found no obvious shorts, and a second 2102 equivalent from a second
manufacturer has the same symptoms.
I connected the debug harness and test 0, the initial "dead board" test, does
show CPU accesses on the red LED and slowly flashes the green LED, so the CPU
at least is alive and can access the test EPROM.
However, test 1, the RAM test, should show long flashes of the green LED if RAM
is bad. I was prepared to see all long flashes which might implicate the
buffers or address decoder, but instead it won't blink the LED at all in that
or any of the other tests. The red LED remains lit and appropriately
extinguishes when the RS button is down.
Again, the board works correctly and fully certifies the other two KIMs.
What would cause it to hang (?) in the RAM test on the defective one?
--
------------------------------------ personal: http://www.cameronkaiser.com/ --
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser(a)floodgap.com
-- Roger Waters to moving crew: "Hey! Careful with those racks, Eugene!" ------
Hi everyone!
I'm having a horrible time trying to find ntpdate pre-compiled for
Irix 5.3 anywhere. Does anyone have a package/tardist?
--
-Jon
+44 7792 149029
I finally got an IBM 5120 earlier this month, to complement the 5100 and
5110 that I already have.
It had a few issues, but I did manage to get it to "boot" to BASIC.
I put together a few notes about it here. Nothing too exciting, but two
things I've learned: (1) the 5120 does actually still have the video
REVERSE feature. (2) the 5120 has both an external (red power switch) and
internal power switch (internal one is at rear below disk drives).
Notes here:
https://voidstar.blog/ibm-5120-aka-ibm-5110-3/
IBM 5120 (aka IBM 5110-3) — voidstar
<https://voidstar.blog/ibm-5120-aka-ibm-5110-3/>
My only question is: how "universal" are 8" disk? This 5120 only came with
a single IBM 8" Diagnostics disk. It looks to be in fine condition, but
I've no idea about the data.
So far I haven't been able to read it - it's probably more hardware/drive
issues, I'm still investigating. But I'm wondering if I had other 8"
disks (3M SS/SD), should I be able to format/MARK them?
I've used old tape decks and 5.25" drives - but 8" drives is all new
territory for me.
Also, I'll be talking about the 5100/5110 at VCF next Sunday on the 25th of
this month, June.
While looking for my RSX11 DECNET manual (because the online version
doesn't have any examples of commands which is why you look in the
manual in the first place) I found a copy of the DSM binder AA-K676B-TK
and ilk.
Is this online or does anyone else have it?
CZ
I've got a few backup sets (potentially incomplete) done on MicroRSX
that were created with BRU on RX50 media. I've cranked out some code to
itemize the contents, but the file types are a mystery. I suppose that
one has to live in that world to know (e.g. MSL)
The sets appear to be (parts) of an incremental backup scheme; I think
I've got at least one copy of the complete set.
Would anyone be willing to have a look at the (ASCII) file catalog and
suggest the application that may have created the files?
Email me offlist if interested.
--Chuck
