[Techtoolslist] Fluke 9010 ram test for 4 bits? Or any non 8 bit wide memory?

[John Robertson]

On 2023/05/28 12:55 p.m., davids at oz.net wrote:
> Have a suspect bad pallet ram on Missile Command, and I see that it is on
> the CPU memory map so I should be able to get to it from the fluke.
>
>   
>
> Now it is only 4 bits wide (and only uses 8 addresses) so I can just do it
> manually but I have seen this on other boards before and never could find a
> way to use the fluke to test these 4 bit rams.
>
>   
>
> Would also assume it could be a problem for 68000 based boards which use
> 16bit wide memory.
>
>   
>
> David

Yes, I've grumbled about this in the past too. Many games ues 5101s for 
battery backup memory andother than poking numbers like AA and 55 at the 
memory space and ready it back it can't be easily tested.

I though of making a simple 4-bit memory device that would cover the 
other data lines and it would also match the memory map for the UUT 
5101, but never got around to it as the AA/55 test worked pretty good 
just picking a few locations. One alternates the test number and reads 
the space one is going to write to make sure the RAM isn't mirroring the 
same data throughout.

It would be nice to make a good 4-bit memory test for the 9010A and the 
9100X - if someone wants to write and share it here I'm sure they would 
earn lots of Karma!

Currently I'm trying to pull the Gottlieb System 80 test out of Ian 
Eure's much appreciated Github archive:

https://github.com/ieure/fluke-9100-disk-archive

to take a look at it (how does it handle the 5101 testing?), I just 
don't have the time at work, and no XP/AT/W95/XT computer at home to 
convert the files into something I can read...

Time, eh, the big enemy!

John :-#)#

PS, I'm going to change TTL so it replies to the list, not the poster, 
it keeps throwing me and I suspect may annoy others. I know it SHOULD do 
a reply to poster, but I prefer these discussions in public unless the 
participants choose to go to private email (which is just fine), so we 
all can benefit from sharing the knowledge, as well as errors made and 
learned from...

>
> _______________________________________________
> Techtoolslist mailing list
> Techtoolslist at flippers.com
> https://pairlist7.pair.net/mailman/listinfo/techtoolslist
> FTP site is: ftp://ftp.flippers.com/TTL/TestEquipment
> Archive site: http://seven.pairlist.net/pipermail/techtoolslist/