HP 1000 A400 repair #HP1000


horniger
 

Hi folks

My name is Rainer an I am a fan of old computers for over 20 years.
My primary interest now is in German computers or computers of German manufacturers but also computer history and historic computers in general.
(see also a part of my collection on my website http://horniger.de/computer/index.html )

My first touch with computers was the HP 97 of my father, when I was a teen. He used it to make simple calculations or just didn't wanted to do all the effort using the UNIVAC of the university for a calculation.
I was and still am fascinated by the red LED display, the sound of the printer and the stack base input (Reverse Polish notation).
Although HP computers were always interesting for me, I never put my focus on them - maybe cause they weren't easy to get.
I now have some in my collection, which found the way to me themselves:
the nice 486er EISA NetServer 4d/66 LM, which I got from a friend and the HP 9000 D Class server, which I got from the company, I worked for.

Then some years ago I was in the company, my girlfriend works for, to have a look at an interesting laboratory database system.
It was running on a HP 1000 A900 machine. A former colleague of my girlfriend was developer of this database system. He knows everything about using and programming the HP 1000 computers (RTE, assembler, fortran,...).
The company (frey) also developed a serial multiplexer for the HP 1000 to connect multiple serial terminals (or laboratory analyzers) to the parallel interface.

A bit of research and I was fascinated in the PDP-11 killer series of HP, which I didn't knew before.
I looked everything the HP 2000 and HP 2100 blinkenlight models from the beginning up to the A990.
A year later, the company wanted to get rid of all the remaining HP 1000 stuff, because the interest in their own history disappeared. This former colleague and now friend asked me and of course I took the rest, which was the A900, an A400, an HO2392A terminal, some external hard disks and two of these multiplexers.

Back then, the A900 had a problem while accessing the SCSI hard disk.
The A400 was setup to show the history of the companies' database system.

Last year, I persuaded this friend, to show the HP 1000 on the VCFB fair (Vintage Computing Festival Berlin), which he did:



I had my own exhibition on this fair, so he had to do all the preparation for the HP 1000 exhibition.

Because I still have little idea of RTE and the HP1000, my friend started to write down a great documentation, starting with the A400 system.
But the suddenly... the A400 CPU stopped working while doing a copy process on the hard disk.
On the next reboot the self-test stopped with all LEDs on, which means "Microcode test Failure" according to the manual.

Although I also want to reactivate the A900 (the complete laboratory database system needs the bigger CPU to have all features running), I now want to get the A400 back to life.

I have an idea of how a computers works and also some experience in repairing computers (soldering... up to logic analyzer - and yes here's another piece of HP equipment: HP 1650B), but no idea of the HP 1000 series in deep.

So here are my questions:
The manual says on teh "Microcode test Failure" error: CPU or powr suppy.
Do you have any tipps how to narrow down the problem?
What tests can I do for thsi?
What can I do for measurements?
How would you start to find the defect(s)?

thank you

Rainer


 

Hi Rainer,

 

The document you’ll need is the ERD (Engineering and Reference Documentation)

Which is an excellent hardware description of  the HP 1000 400A

http://www.bitsavers.org/pdf/hp/1000/A-series/02424-90003_A400_ERD_Jul90.pdf

You’ll also will find a lot of extra info on bitsavers.

 

-Rik

 

Van: VintHPcom@groups.io <VintHPcom@groups.io> Namens horniger
Verzonden: dinsdag 17 november 2020 20:00
Aan: VintHPcom@groups.io
Onderwerp: [VintHPcom] HP 1000 A400 repair #HP1000

 

Hi folks

My name is Rainer an I am a fan of old computers for over 20 years.
My primary interest now is in German computers or computers of German manufacturers but also computer history and historic computers in general.
(see also a part of my collection on my website http://horniger.de/computer/index.html )

My first touch with computers was the HP 97 of my father, when I was a teen. He used it to make simple calculations or just didn't wanted to do all the effort using the UNIVAC of the university for a calculation.
I was and still am fascinated by the red LED display, the sound of the printer and the stack base input (Reverse Polish notation).
Although HP computers were always interesting for me, I never put my focus on them - maybe cause they weren't easy to get.
I now have some in my collection, which found the way to me themselves:
the nice 486er EISA NetServer 4d/66 LM, which I got from a friend and the HP 9000 D Class server, which I got from the company, I worked for.

Then some years ago I was in the company, my girlfriend works for, to have a look at an interesting laboratory database system.
It was running on a HP 1000 A900 machine. A former colleague of my girlfriend was developer of this database system. He knows everything about using and programming the HP 1000 computers (RTE, assembler, fortran,...).
The company (frey) also developed a serial multiplexer for the HP 1000 to connect multiple serial terminals (or laboratory analyzers) to the parallel interface.

A bit of research and I was fascinated in the PDP-11 killer series of HP, which I didn't knew before.
I looked everything the HP 2000 and HP 2100 blinkenlight models from the beginning up to the A990.
A year later, the company wanted to get rid of all the remaining HP 1000 stuff, because the interest in their own history disappeared. This former colleague and now friend asked me and of course I took the rest, which was the A900, an A400, an HO2392A terminal, some external hard disks and two of these multiplexers.

Back then, the A900 had a problem while accessing the SCSI hard disk.
The A400 was setup to show the history of the companies' database system.

Last year, I persuaded this friend, to show the HP 1000 on the VCFB fair (Vintage Computing Festival Berlin), which he did:



I had my own exhibition on this fair, so he had to do all the preparation for the HP 1000 exhibition.

Because I still have little idea of RTE and the HP1000, my friend started to write down a great documentation, starting with the A400 system.
But the suddenly... the A400 CPU stopped working while doing a copy process on the hard disk.
On the next reboot the self-test stopped with all LEDs on, which means "Microcode test Failure" according to the manual.

Although I also want to reactivate the A900 (the complete laboratory database system needs the bigger CPU to have all features running), I now want to get the A400 back to life.

I have an idea of how a computers works and also some experience in repairing computers (soldering... up to logic analyzer - and yes here's another piece of HP equipment: HP 1650B), but no idea of the HP 1000 series in deep.

So here are my questions:
The manual says on teh "Microcode test Failure" error: CPU or powr suppy.
Do you have any tipps how to narrow down the problem?
What tests can I do for thsi?
What can I do for measurements?
How would you start to find the defect(s)?

thank you

Rainer


Glen Slick
 

On Tue, Nov 17, 2020 at 11:19 AM horniger <forum@...> wrote:

But the suddenly... the A400 CPU stopped working while doing a copy process on the hard disk.
On the next reboot the self-test stopped with all LEDs on, which means "Microcode test Failure" according to the manual.

So here are my questions:
The manual says on teh "Microcode test Failure" error: CPU or powr suppy.
Do you have any tipps how to narrow down the problem?
What tests can I do for thsi?
What can I do for measurements?
How would you start to find the defect(s)?
Do you have a device programmer that is capable of reading the
microcode PROMs U1212, U1312, U1412, U1512? Those should be in sockets
and if you can remove them and dump them you could check whether their
contents is still correct. The 4 revisions I see listed in a manual
are:

12100-80010 - 12100-80013,
12100-80015 - 12100-80018,
12100-80019 - 12100-80022,
12100-80023 - 12100-80026.

The last two sets might be identical and the only change is the PROM
supplier from Signetics to Cypress.

I don't know if the contents of the microcode PROMs is already
available online somewhere. I could dump the PROMs from an A400 CPU
that I have. It might take me awhile to get around to doing that.


horniger
 

Thanks for your help and the link. I already know the documents onbitsavers.

Unfortunately there's only a short description of this error, but not how to try to fix.
We checked the voltages, so it seems, that power supply is OK. (We haven't tried to check, if it's stable enogh --> old capacities...)
But how can we find a problem on the CPU board?
Or is it uncommon or not possibile to repair a CPU board instead of replacing?

thanks

Rainer


horniger
 

Thanks again for the tip with the PROMs. This could be a good start...

Are these PROM HP manufactured?
Or do you know which manufacturer and type/ model these PROMs are?

PROMMER/ READER I own are:
- DataIO System19
- Kontron EPP-80
- SUNSHINE EW-70x
- HI-LO systems ALL-11C

thanks

Rainer


 

No, they are standard parts, finding replacements shouldn’t be very difficult.

I think one of your programmers should do the job.

 

-Rik

 

Van: VintHPcom@groups.io <VintHPcom@groups.io> Namens horniger
Verzonden: zondag 29 november 2020 18:40
Aan: VintHPcom@groups.io
Onderwerp: Re: [VintHPcom] HP 1000 A400 repair #HP1000

 

Thanks again for the tip with the PROMs. This could be a good start...

Are these PROM HP manufactured?
Or do you know which manufacturer and type/ model these PROMs are?

PROMMER/ READER I own are:
- DataIO System19
- Kontron EPP-80
- SUNSHINE EW-70x
- HI-LO systems ALL-11C

thanks

Rainer


 

The cpu boards were never meant to be field repairable.

They are field replaceable parts to be exchanged by the service engineer.

Don’t let that knowledge stop you trying to repair the cpu 😉

 

-Rik

 

Van: VintHPcom@groups.io <VintHPcom@groups.io> Namens horniger
Verzonden: zondag 29 november 2020 18:31
Aan: VintHPcom@groups.io
Onderwerp: Re: [VintHPcom] HP 1000 A400 repair #HP1000

 

Thanks for your help and the link. I already know the documents onbitsavers.

Unfortunately there's only a short description of this error, but not how to try to fix.
We checked the voltages, so it seems, that power supply is OK. (We haven't tried to check, if it's stable enogh --> old capacities...)
But how can we find a problem on the CPU board?
Or is it uncommon or not possibile to repair a CPU board instead of replacing?

thanks

Rainer


Glen Slick
 

On Sun, Nov 29, 2020 at 9:40 AM horniger <forum@...> wrote:

Thanks again for the tip with the PROMs. This could be a good start...

Are these PROM HP manufactured?
Or do you know which manufacturer and type/ model these PROMs are?
Some references:

http://www.bitsavers.org/pdf/hp/1000/A-series/02424-90003_A400_ERD_Jul90.pdf
HP 1000 A400 Computer Egnineering and Reference Documentation,
02424-90003, July 1990
Figure 2-10, Control Store Schematic Diagram, Page 2-29/2-30 (Page 48
of the PDF)
This shows the microcode control store PROMs as DM87S421 parts.

http://www.bitsavers.org/components/national/_dataBooks/1987_Non-Volatile_Memory_Databook.pdf
National Semiconductor Non-Volatile Memory Databook, 1987
DM77/87S321, DM77/87S421 (4096 X 8) 32,768-Bit TTL PROMs
Page 3-39 (Page 240 of the PDF)
4K x 8, non-registered, tri-state output

http://www.bitsavers.org/pdf/hp/communicator/1000/5961-6201_Dec-1992.pdf
Communicator/1000 for Software Update 6.0, 5961-6201, December 1992
3.33.1 A400 Base Set Firmware Page 3-104 (Page 230 of the PDF)
The note for the 12100-80023 through 12100-80026 microcode PROM set
says the supplier changed from Signetics to Cypress, in addition to
using National parts.

http://www.bitsavers.org/components/philips/_dataBooks/1990_Philips_IC10_Memories_MOS_TTL_and_ECL_Data_Handbook.pdf
Signetics / Philips Memories MOS, TTL, and ECL Data Handbook, 1990
Signetics/Philips N82LHS321/82LHS321
Page 471 (Page 476 of the PDF)
82LHS321 32K-Bit TTL Bipolar PROM

http://www.bitsavers.org/components/cypress/_dataBooks/1993_Cypress_High-Performance_Data_book.pdf
Cypress Semiconductor High Performance Data Book, 1993
CY7C261/CY7C263/CY7C264 8K X 8 Power-Switched and Reprogrammable PROM
Page 3-64 (Page 575 of the PDF)
The A400 12100 uses the CY7C263 version. (These are only
reprogrammable in the ceramic UV window packages, they are OTP in the
plastic packages).
Note sure if only the high 4K of these 8K parts are used on the A400.
The A400 schematic only shows address A0 through A11 connected to the
PROMs.

My BP Microsystems device programmer explicitly supports the
Signetics/Philips 82LHS321 and the Cypress CY7C263, but not the
National DM87S421 parts. I haven't checked my Data I/O UniSite
supported device list.

For read-only purposes any pin compatible 4KB PROM should work. For
programming you would need to make sure you use the correct
programming algorithm for the device.


Roland Dietiker
 

Hi Rainer

I propose to exchange the VCP EPROMs (U908 U1108, 2764 EEPROMs) and check if the error allready persists. This is the easiest way to exclude an error on VCP EPROMs.

If this not change the situation, let me know which FW revision the board contains: partnumber of the firmware ROMs 12100-800xx (212, U312, U1412, U1512, U208).

 

You could reach me at roland.dietiker@....

 

Best regards

Roland

 

Von: VintHPcom@groups.io [mailto:VintHPcom@groups.io] Im Auftrag von horniger
Gesendet: Sonntag, 29. November 2020 18:40
An: VintHPcom@groups.io
Betreff: Re: [VintHPcom] HP 1000 A400 repair #HP1000

 

Thanks again for the tip with the PROMs. This could be a good start...

Are these PROM HP manufactured?
Or do you know which manufacturer and type/ model these PROMs are?

PROMMER/ READER I own are:
- DataIO System19
- Kontron EPP-80
- SUNSHINE EW-70x
- HI-LO systems ALL-11C

thanks

Rainer


Glen Slick
 

On Sun, Nov 29, 2020 at 9:35 PM Roland Dietiker <roland.dietiker@...> wrote:

Hi Rainer

I propose to exchange the VCP EPROMs (U908 U1108, 2764 EEPROMs) and check if the error allready persists. This is the easiest way to exclude an error on VCP EPROMs.

If this not change the situation, let me know which FW revision the board contains: partnumber of the firmware ROMs 12100-800xx (212, U312, U1412, U1512, U208).
The Communicator/1000 for Software Update 6.0, 5961-6201, December
1992 manual lists these 4 sets of part numbers for the A400 microcode
PROMs U1212 - U1512:

12100-80010 - 12100-80013
12100-80015 - 12100-80018
12100-80019 - 12100-80022
12100-80023 - 12100-80026

As far as I can tell there might actually only be one version of the
microcode for the A400. The different part numbers might just mean
different blank PROM parts, that is 4K x 8 vs 8K x 8, and different
part vendors.

I have one A400 CPU with DM87S421 4K x 8 PROMs screen printed with the
12100-80010 - 12100-80013 part numbers. I dumped the contents of
those PROMs and they are identical matches for the
12100-16005_Rev-4012.src - 12100-16008_Rev-4012.src ASCII-Hex file
format source for those PROMs in the HP 1000 Software Archive. And
those appear to match the A400 microcode source files
12100-18003_Rev-4012.src and 12100-18002_Rev-4012.src and the
assembled listing files 12100-17005_Rev-4012.src and
12100-17006_Rev-4012.src.

I have two A400 CPUs with CY7C263 8K x 8 PROMs (actually OTP EPROMs)
screen printed with the 12100-80023 - 12100-80026 part numbers. I
dumped the contents of those PROMs and they are identical matches for
the 4K x 8 set 12100-80010 - 12100-80013, but with the first 4K half
set to zero in the 8K set. The A400 CPU schematic shows that the CS3 /
A12 pin of the microcode PROM sockets is tied to a +5V pullup so only
the second 4K half of the 8K PROMs is accessed.


Roland Dietiker
 

Hi Glen
Thanks for this useful complementary information about the contents of the Firmware ROM.
I have also found the sources on bitsaver with PN 12100-1xxxxx Rev 4012 as Master Files..

I am missing in the ERD for A400 the Part containing the Part Location on the board and the list with the Replaceable Parts like in the A900 ERD 3-46 and following pages.
It seems not to be planed for this manual.
Did you know where this specific information could be found for A400?

Best regards
Roland

-----Ursprüngliche Nachricht-----
Von: VintHPcom@groups.io [mailto:VintHPcom@groups.io] Im Auftrag von Glen Slick
Gesendet: Montag, 30. November 2020 07:33
An: VintHPcom@groups.io
Betreff: Re: [VintHPcom] HP 1000 A400 repair #HP1000

On Sun, Nov 29, 2020 at 9:35 PM Roland Dietiker <roland.dietiker@...> wrote:

Hi Rainer

I propose to exchange the VCP EPROMs (U908 U1108, 2764 EEPROMs) and check if the error allready persists. This is the easiest way to exclude an error on VCP EPROMs.

If this not change the situation, let me know which FW revision the board contains: partnumber of the firmware ROMs 12100-800xx (212, U312, U1412, U1512, U208).
The Communicator/1000 for Software Update 6.0, 5961-6201, December
1992 manual lists these 4 sets of part numbers for the A400 microcode PROMs U1212 - U1512:

12100-80010 - 12100-80013
12100-80015 - 12100-80018
12100-80019 - 12100-80022
12100-80023 - 12100-80026

As far as I can tell there might actually only be one version of the microcode for the A400. The different part numbers might just mean different blank PROM parts, that is 4K x 8 vs 8K x 8, and different part vendors.

I have one A400 CPU with DM87S421 4K x 8 PROMs screen printed with the
12100-80010 - 12100-80013 part numbers. I dumped the contents of those PROMs and they are identical matches for the 12100-16005_Rev-4012.src - 12100-16008_Rev-4012.src ASCII-Hex file format source for those PROMs in the HP 1000 Software Archive. And those appear to match the A400 microcode source files 12100-18003_Rev-4012.src and 12100-18002_Rev-4012.src and the assembled listing files 12100-17005_Rev-4012.src and 12100-17006_Rev-4012.src.

I have two A400 CPUs with CY7C263 8K x 8 PROMs (actually OTP EPROMs) screen printed with the 12100-80023 - 12100-80026 part numbers. I dumped the contents of those PROMs and they are identical matches for the 4K x 8 set 12100-80010 - 12100-80013, but with the first 4K half set to zero in the 8K set. The A400 CPU schematic shows that the CS3 /
A12 pin of the microcode PROM sockets is tied to a +5V pullup so only the second 4K half of the 8K PROMs is accessed.


Glen Slick
 

On Mon, Nov 30, 2020 at 12:27 AM Roland Dietiker <roland.dietiker@...> wrote:

I am missing in the ERD for A400 the Part containing the Part Location on the board and the list with the Replaceable Parts like in the A900 ERD 3-46 and following pages.
It seems not to be planed for this manual.
Did you know where this specific information could be found for A400?
It does seem odd that the A400 ERD includes parts locations and parts
lists for the 12103 memory array cards but not for the A400 12100 CPU
card.

There are approximately 100 DIP packages on the A400 12100 CPU card.
It might not take too much effort to take a high resolution scan of a
12100 card and use that to create a parts location diagram and a parts
list of the DIP and ASIC packages. It would also be nice to create a
cross reference from the DIP parts to grid locators on the schematics.
Maybe something I can work on as time permits.

The A400 ERD does include the following, plus additional backplane and
power supply information not listed below:

HP 1000 A400 Computer
Egnineering and Reference Documentation
02424-90003, July 1990
http://www.bitsavers.org/pdf/hp/1000/A-series/02424-90003_A400_ERD_Jul90.pdf

Chapter 2, A400 Board Operation

Figure 2-3, Page 2-15, Backplane Buffers and Clocks, Sheet 1 of 13
Figure 2-4, Page 2-17, Memory Control, Sheet 2 of 13
Figure 2-5, Page 2-19, CIL, Addr Reg, Map & Boot RAM, Sheet 3 of 13
Figure 2-6, Page 2-21, Data Path & Parity Generation, Sheet 4 of 13
Figure 2-7, Page 2-23, Address Path, Sheet 5 of 13
Figure 2-8, Page 2-25, Low Byte of RAM Array, Sheet 6 of 13
Figure 2-9, Page 2-27, Parity Bit & High Byte of RAM Array, Sheet 7 of 13
Figure 2-10, Page 2-29, Control Store, Sheet 8 of 13
Figure 2-11, Page 2-31, Processor & Memory Connections, Sheet 9 of 13
Figure 2-12, Page 2-33, Processor I.C. & Bypass Capacitors, Sheet 10 of 13

Chapter 5, On-Board I/O

Figure 5-10, Page 5-23, I/O Section I/O Master, Sheet 11 of 13
Figure 5-11, Page 5-25, I/O Section Port Processors, Sheet 12 of 13
Figure 5-12, Page 5-27, I/O Section I/O Circuits, Sheet 13 of 13

Chapter 6 Memory Arrays

Figure 6-3, Page 6-31, 12103C Parts Locations
Table 6-2, Page 6-32, 12103C Parts List

Figure 6-4, Page 6-35, 12103D Parts Locations
Table 6-3, Page 6-36, 12103D Parts List

Figure 6-5, Page 6-40, 12103K/L/M Parts Locations
Table 6-4, Page 6-41, 12103K Parts List
Table 6-5, Page 6-43, 12103L Parts List
Table 6-6, Page 6-46, 12103M Parts List

Page 6-51, 12103A/B/C Memory Array, Sheet 1 of 2
Page 6-53, 12103A/B/C Memory Array, Sheet 2 of 2

Page 6-55, 12103D Memory Array, Sheet 1 of 3
Page 6-57, 12103D Memory Array, Sheet 2 of 3
Page 6-59, 12103D Memory Array, Sheet 3 of 3

Page 6-61, 12103K/L/M Memory Array, Sheet 1 of 7
Page 6-63, 12103K/L/M Memory Array, Sheet 2 of 7
Page 6-65, 12103K/L/M Memory Array, Sheet 3 of 7
Page 6-67, 12103K/L/M Memory Array, Sheet 4 of 7
Page 6-69, 12103K/L/M Memory Array, Sheet 5 of 7
Page 6-71, 12103K/L/M Memory Array, Sheet 6 of 7
Page 6-73, 12103K/L/M Memory Array, Sheet 7 of 7