Re: DEC KA650 VAX memory troubleshooting

[Glen Slick via cctalk]

Those waveform window displays are from an HP / Agilent 16700 series logic
analyzer.  Easy to recognize the HP-UX U/I if you have used one.

On Sun, Nov 24, 2019, 6:46 AM W2HX via cctalk  wrote:

> Wow. Very nicely done! Which logic analyzer did you use to capture those
> displays?
>
> 73 Eugene W2HX
> 
> From: cctalk  on behalf of Joseph Zatarski
> via cctalk 
> Sent: Sunday, November 24, 2019 1:28 AM
> To: General Discussion: On-Topic Posts
> Subject: Re: DEC KA650 VAX memory troubleshooting
>
> Well, I finally got around to posting this on the CHWiki, in case
> anybody was curious about this.
>
> https://gunkies.org/wiki/DEC_KA650_Memory_Subsystem
>

Re: DEC KA650 VAX memory troubleshooting

[Joseph Zatarski via cctalk]

I used an HP 16700A, which you can see in the video I linked some time back:

https://youtu.be/eDMhdAEFEgc

On 11/24/19 8:27 AM, W2HX wrote:

Wow. Very nicely done! Which logic analyzer did you use to capture those 
displays?

73 Eugene W2HX

From: cctalk  on behalf of Joseph Zatarski via cctalk 

Sent: Sunday, November 24, 2019 1:28 AM
To: General Discussion: On-Topic Posts
Subject: Re: DEC KA650 VAX memory troubleshooting

Well, I finally got around to posting this on the CHWiki, in case
anybody was curious about this.

https://gunkies.org/wiki/DEC_KA650_Memory_Subsystem

On 6/17/19 7:56 PM, Joe Zatarski wrote:

OK, so where should a thing like this go: https://pastebin.com/taQwaTV6

Anybody got a decent place to upload that? it's my notes on the
MS650-AA, and more generally the KA650 CMCTL memory subsystem.

Includes my theory of operation of the CMCTL, the organization of
memory, the ECC equations (kinda, the info is there to derive them),
explanations of the signals on the memory bus, and most importantly, a
list of which bits and RAM regions correspond to the 312 DRAMs on the board.

On Sat, Jun 15, 2019 at 8:33 PM Joe Zatarski mailto:joezatar...@gmail.com>> wrote:
  >
  > Hey Everyone,
  >
  > I just thought I'd share a video of how I'm going about
troubleshooting the bad DRAMs on my MS650 memory board.
  >
  > https://youtu.be/eDMhdAEFEgc
  >
  > I apologize for the shaky-cam, I don't have a tripod, and I needed to
do a lot of panning anyway.
  >
  > I will be sharing my notes on the MS650 once I have a chance to write
them up properly as well. I wasn't able to find a printset for the RAM
card itself, so I assume one doesn't exist in digital form yet. I have
documented what bit and memory range each DRAM on the card corresponds
to, which may help someone troubleshooting in the future
  >
  > Regards,
  > Joe Zatarski

Re: DEC KA650 VAX memory troubleshooting

[W2HX via cctalk]

Wow. Very nicely done! Which logic analyzer did you use to capture those 
displays?

73 Eugene W2HX

From: cctalk  on behalf of Joseph Zatarski via 
cctalk 
Sent: Sunday, November 24, 2019 1:28 AM
To: General Discussion: On-Topic Posts
Subject: Re: DEC KA650 VAX memory troubleshooting

Well, I finally got around to posting this on the CHWiki, in case
anybody was curious about this.

https://gunkies.org/wiki/DEC_KA650_Memory_Subsystem

On 6/17/19 7:56 PM, Joe Zatarski wrote:
> OK, so where should a thing like this go: https://pastebin.com/taQwaTV6
>
> Anybody got a decent place to upload that? it's my notes on the
> MS650-AA, and more generally the KA650 CMCTL memory subsystem.
>
> Includes my theory of operation of the CMCTL, the organization of
> memory, the ECC equations (kinda, the info is there to derive them),
> explanations of the signals on the memory bus, and most importantly, a
> list of which bits and RAM regions correspond to the 312 DRAMs on the board.
>
> On Sat, Jun 15, 2019 at 8:33 PM Joe Zatarski  <mailto:joezatar...@gmail.com>> wrote:
>  >
>  > Hey Everyone,
>  >
>  > I just thought I'd share a video of how I'm going about
> troubleshooting the bad DRAMs on my MS650 memory board.
>  >
>  > https://youtu.be/eDMhdAEFEgc
>  >
>  > I apologize for the shaky-cam, I don't have a tripod, and I needed to
> do a lot of panning anyway.
>  >
>  > I will be sharing my notes on the MS650 once I have a chance to write
> them up properly as well. I wasn't able to find a printset for the RAM
> card itself, so I assume one doesn't exist in digital form yet. I have
> documented what bit and memory range each DRAM on the card corresponds
> to, which may help someone troubleshooting in the future
>  >
>  > Regards,
>  > Joe Zatarski

Re: DEC KA650 VAX memory troubleshooting

[Joseph Zatarski via cctalk]

Well, I finally got around to posting this on the CHWiki, in case 
anybody was curious about this.


https://gunkies.org/wiki/DEC_KA650_Memory_Subsystem

On 6/17/19 7:56 PM, Joe Zatarski wrote:

OK, so where should a thing like this go: https://pastebin.com/taQwaTV6

Anybody got a decent place to upload that? it's my notes on the 
MS650-AA, and more generally the KA650 CMCTL memory subsystem.


Includes my theory of operation of the CMCTL, the organization of 
memory, the ECC equations (kinda, the info is there to derive them), 
explanations of the signals on the memory bus, and most importantly, a 
list of which bits and RAM regions correspond to the 312 DRAMs on the board.


On Sat, Jun 15, 2019 at 8:33 PM Joe Zatarski > wrote:

 >
 > Hey Everyone,
 >
 > I just thought I'd share a video of how I'm going about 
troubleshooting the bad DRAMs on my MS650 memory board.

 >
 > https://youtu.be/eDMhdAEFEgc
 >
 > I apologize for the shaky-cam, I don't have a tripod, and I needed to 
do a lot of panning anyway.

 >
 > I will be sharing my notes on the MS650 once I have a chance to write 
them up properly as well. I wasn't able to find a printset for the RAM 
card itself, so I assume one doesn't exist in digital form yet. I have 
documented what bit and memory range each DRAM on the card corresponds 
to, which may help someone troubleshooting in the future

 >
 > Regards,
 > Joe Zatarski

Re: DEC KA650 VAX memory troubleshooting (video)

[Antonio Carlini via cctalk]

On 18/06/2019 01:56, Joe Zatarski via cctech wrote:

OK, so where should a thing like this go: https://pastebin.com/taQwaTV6

Anybody got a decent place to upload that? it's my notes on the MS650-AA,
and more generally the KA650 CMCTL memory subsystem.

Includes my theory of operation of the CMCTL, the organization of memory,
the ECC equations (kinda, the info is there to derive them), explanations
of the signals on the memory bus, and most importantly, a list of which
bits and RAM regions correspond to the 312 DRAMs on the board.



Sounds ideal for the Computer History Wiki: 
http://gunkies.org/wiki/Main_Page.



Antonio



--
Antonio Carlini
anto...@acarlini.com

Re: DEC KA650 VAX memory troubleshooting (video)

[Noel Chiappa via cctalk]

> From: Joe Zatarski

> OK, so where should a thing like this go: ... Anybody got a decent
> place to upload that?

As always, the CHWiki is available for any vintage computer stuff. I can
set up an account for anyone here who wants one.

I have posted similar information for PDP-11 memory, e.g. here:

  http://gunkies.org/wiki/QBUS_memories#Diagnosing_DRAM_memory_failures
  http://gunkies.org/wiki/MSV11-J#Technical_information

which seems to be a direct analogue of the stuff you have.

Noel

Re: DEC KA650 VAX memory troubleshooting (video)

[Joe Zatarski via cctalk]

OK, so where should a thing like this go: https://pastebin.com/taQwaTV6

Anybody got a decent place to upload that? it's my notes on the MS650-AA,
and more generally the KA650 CMCTL memory subsystem.

Includes my theory of operation of the CMCTL, the organization of memory,
the ECC equations (kinda, the info is there to derive them), explanations
of the signals on the memory bus, and most importantly, a list of which
bits and RAM regions correspond to the 312 DRAMs on the board.

On Sat, Jun 15, 2019 at 8:33 PM Joe Zatarski  wrote:
>
> Hey Everyone,
>
> I just thought I'd share a video of how I'm going about troubleshooting
the bad DRAMs on my MS650 memory board.
>
> https://youtu.be/eDMhdAEFEgc
>
> I apologize for the shaky-cam, I don't have a tripod, and I needed to do
a lot of panning anyway.
>
> I will be sharing my notes on the MS650 once I have a chance to write
them up properly as well. I wasn't able to find a printset for the RAM card
itself, so I assume one doesn't exist in digital form yet. I have
documented what bit and memory range each DRAM on the card corresponds to,
which may help someone troubleshooting in the future
>
> Regards,
> Joe Zatarski

Re: DEC KA650 VAX memory troubleshooting (video)

[Joe Zatarski via cctalk]

sorry, the technical manual actually, which has an architecture *chapter*
http://www.bitsavers.org/pdf/dec/vax/650/

The idea, eventually, is that I will publish my notes so that you wouldn't
need the logic analyzer, at least for the 8MB board. I just had it hooked
up, so I demoed it. The notes will include a mapping of bits and adresses
to ICs so that you can narrow down which chip from just the ROM monitor. I
don't have a 16MB board, but somebody could honestly probably figure out
the mapping with a logic probe if they had to, just probe /cas while
writing various test addresses, then check the data line while writing
various test patterns. I also came up with some data that produces useful
ECC bits, like all 1s, all 0s, one bit set only, and one bit clear only.
That will also be in the notes when I write it up.


On Sun, Jun 16, 2019, 3:25 AM Rob Jarratt 
wrote:

> That is really interesting, sadly I don't have quite as much gear as you,
> I only have a basic logic analyser, but I am not currently trying to fix a
> MS650 memory board. You mentioned a KA650 architecture manual and you had a
> PDF of it in the video. I couldn't find it on Manx? Where can I find it?
>
> Thanks
>
> Rob
>
> > -Original Message-
> > From: cctech  On Behalf Of Joe Zatarski
> via
> > cctech
> > Sent: 16 June 2019 02:33
> > To: cct...@classiccmp.org
> > Subject: DEC KA650 VAX memory troubleshooting (video)
> >
> > Hey Everyone,
> >
> > I just thought I'd share a video of how I'm going about troubleshooting
> the
> > bad DRAMs on my MS650 memory board.
> >
> > https://youtu.be/eDMhdAEFEgc
> >
> > I apologize for the shaky-cam, I don't have a tripod, and I needed to do
> a lot
> > of panning anyway.
> >
> > I will be sharing my notes on the MS650 once I have a chance to write
> them
> > up properly as well. I wasn't able to find a printset for the RAM card
> itself, so I
> > assume one doesn't exist in digital form yet. I have documented what bit
> and
> > memory range each DRAM on the card corresponds to, which may help
> > someone troubleshooting in the future
> >
> > Regards,
> > Joe Zatarski
>
>

RE: DEC KA650 VAX memory troubleshooting (video)

[Rob Jarratt via cctalk]

That is really interesting, sadly I don't have quite as much gear as you, I 
only have a basic logic analyser, but I am not currently trying to fix a MS650 
memory board. You mentioned a KA650 architecture manual and you had a PDF of it 
in the video. I couldn't find it on Manx? Where can I find it?

Thanks

Rob

> -Original Message-
> From: cctech  On Behalf Of Joe Zatarski via
> cctech
> Sent: 16 June 2019 02:33
> To: cct...@classiccmp.org
> Subject: DEC KA650 VAX memory troubleshooting (video)
> 
> Hey Everyone,
> 
> I just thought I'd share a video of how I'm going about troubleshooting the
> bad DRAMs on my MS650 memory board.
> 
> https://youtu.be/eDMhdAEFEgc
> 
> I apologize for the shaky-cam, I don't have a tripod, and I needed to do a lot
> of panning anyway.
> 
> I will be sharing my notes on the MS650 once I have a chance to write them
> up properly as well. I wasn't able to find a printset for the RAM card 
> itself, so I
> assume one doesn't exist in digital form yet. I have documented what bit and
> memory range each DRAM on the card corresponds to, which may help
> someone troubleshooting in the future
> 
> Regards,
> Joe Zatarski