Tektronix 4052/54 diagnostic ROM pack remade.

[stepleton]

Apologies if this has been pointed out before, but Tektronix liked to use those miserable TI "side-wiper" IC sockets which many people find unreliable, and I can see some empty ones on your circuit board. You might want to include the possibility of a faulty socket in your troubleshooting.

 

[nikola-wan]

There are no patch ROMs on the MAS board, here's a photo: https://www.electronixandmore.com/resources/teksystem/boardbottom.jpg

I'll try Jos's WSI 57C49 ROM upgrade. Unfortunately in the process of debugging my 4052, the repeated power cycling killed the deflection power supplies so now I get a dot in the center of the screen and have a new problem to fix.

Meanwhile, I ordered a set of 57C49's and will need to find or build a programmer for them.

I'm not 100% convinced there isn't a failing DRAM on the board because the nature of the errors and hangs with the diagnostics pack or even running programs off the GPIB drive are random and not repeatable.

Wow - I see a board tested date of May 1979 on your MAS board! It must be one of the first ones produced - which is why you have the V2.1 ROMs and no patch ROMs!

I have a working Data I/O 29B with Unipak 2, so I should be able to program the 57C49's for you.

I also had the dot in the center of the screen on my 4054A, but the problem was not the deflection amplifier, it was in the high voltage power supply - an open resistor - see my post here:
https://forum.vcfed.org/index.php?threads/tektronix-4054a-with-bicolor-dvst-bright-orange-spot-when-screen-dims-issue.1246170/post-1376450

 

[nikola-wan]

There are no patch ROMs on the MAS board, here's a photo: https://www.electronixandmore.com/resources/teksystem/boardbottom.jpg

I'll try Jos's WSI 57C49 ROM upgrade. Unfortunately in the process of debugging my 4052, the repeated power cycling killed the deflection power supplies so now I get a dot in the center of the screen and have a new problem to fix.

Meanwhile, I ordered a set of 57C49's and will need to find or build a programmer for them.

I'm not 100% convinced there isn't a failing DRAM on the board because the nature of the errors and hangs with the diagnostics pack or even running programs off the GPIB drive are random and not repeatable.

The 4052/4052A plus 4054/4054A Technical Data manual is here:
https://bitsavers.trailing-edge.com/pdf/tektronix/405x/070-2840-03_4052-4054A_Service_Manual_Technical_Data_198211.pdf

The 4052/4052A Parts and Schematics manual is in two pdf files since the schematics in sections 7-9 are much bigger pages:
https://w140.com/tekwiki/images/0/0e/070-2829-01_sections_1-6.pdf
and
https://w140.com/tekwiki/images/e/e1/070-2829-01_sections_7-9.pdf

 

[jbstan]

Wow - I see a board tested date of May 1979 on your MAS board! It must be one of the first ones produced - which is why you have the V2.1 ROMs and no patch ROMs!

I have a working Data I/O 29B with Unipak 2, so I should be able to program the 57C49's for you.

I also had the dot in the center of the screen on my 4054A, but the problem was not the deflection amplifier, it was in the high voltage power supply - an open resistor - see my post here:
https://forum.vcfed.org/index.php?threads/tektronix-4054a-with-bicolor-dvst-bright-orange-spot-when-screen-dims-issue.1246170/post-1376450

I fixed my 4052 display issue and am back in business. I posted about it in a different but more related thread: https://forum.vcfed.org/index.php?threads/tektronix-4052-troubleshooting.64617/post-1455311

My problem with the 4052 was indeed a deflection circuit failure due to a failed vias disconnecting -20V from the deflection amplifiers causing no deflection in 3 out of 4 quadrants on the display.

The 4054 issue with the dot in the center is different because the XY display portion was drawing characters just fine, it was during idle when the XY deflection was presumably at 0 (center of screen) but the Z axis wasn't blanking the gun properly as you had found.

Now back to where I had left off, I ran the GPIB drive and see "GP INTERFACE BUS I/O ERROR IN LINE 215 - MESSAGE NUMBER 69" that show up randomly. I don't know if this is due to the v2.1 BASIC ROMs, but why would it not be a DRAM issue? Also as I had mentioned earlier, the diagnostics pack would hang. I repopulated the upper 32KB of tested good 4116 DRAMs after finding 1 failed chip and ran the diagnostics RAM test using CALL "RAMTST" ... short RAM test passed, long RAM test after the LEDs on the diagnostics board counted up to all xFF, I saw an "ERROR HANG" print out: https://electronixandmore.com/resources/teksystem/tek_ramtst_errorhang.jpg

 

[nikola-wan]

I fixed my 4052 display issue and am back in business. I posted about it in a different but more related thread: https://forum.vcfed.org/index.php?threads/tektronix-4052-troubleshooting.64617/post-1455311

My problem with the 4052 was indeed a deflection circuit failure due to a failed vias disconnecting -20V from the deflection amplifiers causing no deflection in 3 out of 4 quadrants on the display.

The 4054 issue with the dot in the center is different because the XY display portion was drawing characters just fine, it was during idle when the XY deflection was presumably at 0 (center of screen) but the Z axis wasn't blanking the gun properly as you had found.

Now back to where I had left off, I ran the GPIB drive and see "GP INTERFACE BUS I/O ERROR IN LINE 215 - MESSAGE NUMBER 69" that show up randomly. I don't know if this is due to the v2.1 BASIC ROMs, but why would it not be a DRAM issue? Also as I had mentioned earlier, the diagnostics pack would hang. I repopulated the upper 32KB of tested good 4116 DRAMs after finding 1 failed chip and ran the diagnostics RAM test using CALL "RAMTST" ... short RAM test passed, long RAM test after the LEDs on the diagnostics board counted up to all xFF, I saw an "ERROR HANG" print out: https://electronixandmore.com/resources/teksystem/tek_ramtst_errorhang.jpg

The latest 4050 BASIC Reference booklet I scanned: http://www.bitsavers.org/pdf/tektronix/405x/070-2142-02_Tek_4050_Series_Basic_Reference_Jun83.pdf includes the 4050A BASIC commands and ERRORS and indicates error 69 is "both NDAC and NRFD signal lines are inactive high, which is an illegal GPIB state. This usually means there are no peripheral devices connected to the GPIB". Since you are running one of my Flash Drive BASIC programs - I don't think the Flash Drive is the problem as long as your Flash Drive is running the latest Arduino code: https://github.com/mmcgraw74/Tektronix-4050-GPIB-Flash-Drive/tree/master/Arduino_Code. It could still be BASIC ROM v2.1 GPIB handling. I have not found a document listing bugs in each 4052/4054 ROM firmware release. The ERROR HANG in the Diagnostic ROM Pack long RAM test is decisive - most likely you have a DRAM issue in the soldered bank of DRAM. I think your best bet is to remove all the DRAM and replace with sockets, then reinstall your original DRAM - replacing one at a time to fix the issue. I have done this and highly recommend using solder removal braid and a small tip soldering iron to reduce the chance of lifting a pad as the pads are quite narrow on the MAS board. I dip the solder removal braid in flux before heating it on top of the pad to increase the amount of solder removed. I do have to clean the IC pads after the IC is removed with isopropyl alcohol or flux remover spray. I don't recommend a solder sucker as these MAS IC solder pads are so narrow- the sucker may remove the entire pad along with the feedthrough

 

[jbstan]

I went ahead and desoldered the lower 9 DRAM chips from the PCB, I tried wicking at first but found the solder sucker and a reflow gun worked effectively without damaging traces. I ran all 9 desoldered chips through my little DRAM tester and found 2/9 were bad. I soldered in sockets and installed good chips. I haven't removed the upper 9 chips yet. I ran the DRP "RAMTST" procedure again, this time it showed short and long ram test, finished and flashed the screen then reprinted "4052/54 CRC/RAMTST ROMPACK V1.1 Memory Size is DFFF" and hung right there. According to the DRP manual, if any test completed successfully, it should have printed "DONE" at the end and not hang. Can anyone confirm that? Also for what it's worth, the GPIB drive still has random GPIB errors. I think I will need to desolder the upper 9 chips next.

 

[nikola-wan]

I went ahead and desoldered the lower 9 DRAM chips from the PCB, I tried wicking at first but found the solder sucker and a reflow gun worked effectively without damaging traces. I ran all 9 desoldered chips through my little DRAM tester and found 2/9 were bad. I soldered in sockets and installed good chips. I haven't removed the upper 9 chips yet. I ran the DRP "RAMTST" procedure again, this time it showed short and long ram test, finished and flashed the screen then reprinted "4052/54 CRC/RAMTST ROMPACK V1.1 Memory Size is DFFF" and hung right there. According to the DRP manual, if any test completed successfully, it should have printed "DONE" at the end and not hang. Can anyone confirm that? Also for what it's worth, the GPIB drive still has random GPIB errors. I think I will need to desolder the upper 9 chips next.

I confirm that the 4052 Diagnostic ROM test for RAM will print DONE and not hang - see the second photo in my post from 2018.

I will bet you have another bad DRAM or two in the upper set of 9 soldered chips.

 

[jdreesen]

>>> I have 20 PCB's, which is probably enough for the next 25 years....

All gone now, did not expect to ever run out of them....

ATM I cannot ship anything to the US, and it looks like thereafter there will be a 200 USD import surcharge on anything shipped from CH to US.
I therefore will no longer supply these, so here are the Gerbers, maybe someone in the US can make some and distribute them over there to whomever needs them.
Note that these PCBs will need some mechanical fitting, i.e. they are rectangular and need trimming in the connector area. They were my first Kicad experiments....

Jos

 

[nikola-wan]

Sorry to hear that Jos!

If anyone in the US needs a 4052 Diagnostic ROM Pack (remade) for their 4052/4052A or 4054/4054A leave a reply to this post.

 

[nikola-wan]

Jos, when I import your zip file into JLCPCB the board has too much width?

 

[jbstan]

Update since July - I've replaced all the soldered DRAMs with sockets and found 1 more faulty DRAM. The diagnostics pack, however, did not quite pass the RAM tests perfectly, it'd complete but not print DONE. I tested the DRAMs again individually in a 4116 tester and double-checked they were good. Before troubleshooting further, I decided to wait until I upgraded the ROMs from v2.1 to v5.1. With Monty's help, I received a set of programmed 57C49's and installed them today. The system powered up to a blinking cursor so that's at least a good sign. I took a leap of faith and tried to load the GPIB drive. Ran into a system error! The v2.1 ROMs only gave me random GPIB IO errors, but never a system error.



I then set up the diagnostics pack to run the ROM CRC tests.... system went haywire after testing U880.


Shortly after that, the screen flashes and it prints a system error at the bottom.

There are no patch PLAs or ROMs installed on this board. Only the set of 8 57C49 ROMs.

 

[jdreesen]

What do the LED's on the Diagnostic pack say ? The original docu from Tektronix shows their meaning, but keep in mind that my reproduction has these LED's in the wrong order (right to left iso left to right)

 

[nikola-wan]

Update since July - I've replaced all the soldered DRAMs with sockets and found 1 more faulty DRAM. The diagnostics pack, however, did not quite pass the RAM tests perfectly, it'd complete but not print DONE. I tested the DRAMs again individually in a 4116 tester and double-checked they were good. Before troubleshooting further, I decided to wait until I upgraded the ROMs from v2.1 to v5.1. With Monty's help, I received a set of programmed 57C49's and installed them today. The system powered up to a blinking cursor so that's at least a good sign. I took a leap of faith and tried to load the GPIB drive. Ran into a system error! The v2.1 ROMs only gave me random GPIB IO errors, but never a system error.

View attachment 1307604

I then set up the diagnostics pack to run the ROM CRC tests.... system went haywire after testing U880.

View attachment 1307605
Shortly after that, the screen flashes and it prints a system error at the bottom.
View attachment 1307606
There are no patch PLAs or ROMs installed on this board. Only the set of 8 57C49 ROMs.

Jon,

The SYSTEM ERRORs can be decoded - see my post: 4052/4054 System Error Messages

The first error occurs after using the Flash Drive to find and then load file 1 "Root Menu Loader" length 1427

• The 00 means SYSTEM ROM, the 10Eh decodes to BASIC line# 270.
• Line 270 in that file is:
  • 270 READ C$,T1,S9,T8
  • which is reading one of the DATA statements in lines 210-240.

When a BASIC program is OLDed into RAM, the BASIC ROM converts the data into 4050 format string or numeric SYSTEM variables.
The READ statement in 270 is simply copying the SYSTEM variables into USER variable names.

Simple BASIC operation - so I suspect you still have at least one flaky DRAM.

The SYSTEM ERROR is a fatal interrupt - and could be caused by a RAM parity error.

Have you run the LONG RAM test in the DRP?

 

[nikola-wan]

Update since July - I've replaced all the soldered DRAMs with sockets and found 1 more faulty DRAM. The diagnostics pack, however, did not quite pass the RAM tests perfectly, it'd complete but not print DONE. I tested the DRAMs again individually in a 4116 tester and double-checked they were good. Before troubleshooting further, I decided to wait until I upgraded the ROMs from v2.1 to v5.1. With Monty's help, I received a set of programmed 57C49's and installed them today. The system powered up to a blinking cursor so that's at least a good sign. I took a leap of faith and tried to load the GPIB drive. Ran into a system error! The v2.1 ROMs only gave me random GPIB IO errors, but never a system error.

View attachment 1307604

I then set up the diagnostics pack to run the ROM CRC tests.... system went haywire after testing U880.

View attachment 1307605
Shortly after that, the screen flashes and it prints a system error at the bottom.
View attachment 1307606
There are no patch PLAs or ROMs installed on this board. Only the set of 8 57C49 ROMs.

Your DRP CRC list picture shows something very odd:

the line with U870B - should show U870A as in Jos Dreesen's post #1 with his 4052 v5.1 ROM CRCs in this thread: https://forum.vcfed.org/index.php?threads/tektronix-4052-54-diagnostic-rom-pack-remade.63974/post-63974



I will bet this is a RAM error in low RAM - might have caused a parity error when it was read and printed back to the display.
Maybe the soldered RAM LSB? Not sure which LSB - could be upper byte or lower byte.

DRP Long RAM test should find the bad RAM.

 

[jbstan]

DRP Long RAM test appears to behave oddly, same as before, 4 out of 7 times I ran it, I get a "DONE" no problem. 2 times the RAM test finished but instead of printing "DONE", the screen flashes and the test repeats. 1 time the RAM test finished, flashed the screen, and hung - in this case, the DRP LEDs indicated an unexpected IRQ from the ALU or I/O.

When the RAM test completed and printed "DONE", I ran the CRC test and was able to get a complete listing with matching CRCs except for ROMs past U893.

Since it wasn't clear if there's a flaky DRAM anywhere despite testing every individual 4116, I pulled all the lower 32KB DRAMs that were a mix of Tektronix originals and newer chips, and put in all newer/tested DRAMs. The observed long RAM behaviors still persist where intermittently the DRP would repeat the test rather than complete with a "DONE" message. Also running the GPIB drive still returns a system error.

 

[nikola-wan]

DRP Long RAM test appears to behave oddly, same as before, 4 out of 7 times I ran it, I get a "DONE" no problem. 2 times the RAM test finished but instead of printing "DONE", the screen flashes and the test repeats. 1 time the RAM test finished, flashed the screen, and hung - in this case, the DRP LEDs indicated an unexpected IRQ from the ALU or I/O.

When the RAM test completed and printed "DONE", I ran the CRC test and was able to get a complete listing with matching CRCs except for ROMs past U893.
View attachment 1307862
Since it wasn't clear if there's a flaky DRAM anywhere despite testing every individual 4116, I pulled all the lower 32KB DRAMs that were a mix of Tektronix originals and newer chips, and put in all newer/tested DRAMs. The observed long RAM behaviors still persist where intermittently the DRP would repeat the test rather than complete with a "DONE" message. Also running the GPIB drive still returns a system error.

Your ROM CRC test is now perfectly fine!

The 4052 Diagnostic ROM Pack firmware CRC results stopped at v4.3 and you now have v5.1.

This Service Note shows the v5.1 was the last version for the 4052/4054 and your CRC results match the entire list on page 18 for v5.1!
4052-4054 FW info July 1983.pdf

When you ran the RAM test - was the Flash Drive also plugged into the GPIB connector?

Since you built the Flash Drive yourself and had bootloader problems, I wonder if the Arduino Flash Drive program was loaded properly.

If you ship your Flash Drive to me I will test it on my 4052 and 4054A computers and see if it duplicates the errors you are seeing.

If it does - I will try to program it like I do for my assembled Flash Drive boards and see if that helps.

 

[nikola-wan]

Wow - I see a board tested date of May 1979 on your MAS board! It must be one of the first ones produced - which is why you have the V2.1 ROMs and no patch ROMs!

I have a working Data I/O 29B with Unipak 2, so I should be able to program the 57C49's for you.

I also had the dot in the center of the screen on my 4054A, but the problem was not the deflection amplifier, it was in the high voltage power supply - an open resistor - see my post here:
https://forum.vcfed.org/index.php?threads/tektronix-4054a-with-bicolor-dvst-bright-orange-spot-when-screen-dims-issue.1246170/post-1376450

Looking at your MAS board photo again, I see several 'blue' wires that do NOT look like they were factory installed.

The 4052/4054 MAS board was revised eight times according to the MAS schematic sheet A6-5 in the 4054-4054A parts and schematics 070-2839-03 pdf page 377 which also has a note:

"SEE PARTS LIST FOR EARLIER VALUES AND SERIAL NUMBER RANGES OF PARTS OUTLINED OR DEPICTED IN GREY"

Since your 4052 MAS board is dated 1979 which was the start of 4052 production - it may have issues that were corrected in later board revisions.

What is the serial number of your 4052 and the MAS board part number with version?


Here are two photos of my 4052 MAS board with 4052 I/O board plugged into the top of the MAS board:



I found another photo of my 4052 MAS board and see the part number is: 670-6030-09



My I/O board is a -01 and an inspection sticker indicates 1980.

But I don't see the jumper wires that are on your MAS board on my MAS board and it looks like my MAS board is a different PCB. Look at the two ICs above the part with the label "033900" that have a green wire between them.

On your MAS board there is only one IC in that area above the IC with the label.

 

[nikola-wan]

The 4054-4054A parts and schematics 070-2839-03 manual is dated July 1982 and shows 670-6030-01 through -07 serial number range for 4054. The 4054A had a different MAS board with EPROMs.
The 4052-4052A parts and schematics 070-2829-01 manual is dated Aug 1983 and shows 670-6030-00 through -08 serial number range for 4052. The 4052A used the same MAS board as the 4054A.

Here is the 4052 MAS board version versus serial number list (yellow box):



Interesting serial number for discontinuing the -00 board. I doubt Tektronix sold 9899 4052 computers with -00 rev boards.
Possibly they changed the PCB for the -01 board and decided to start a new serial number range at B020000?

If the 4052 serial number count was sequential with no more gaps from B20000 - then through Aug 1983 they produced 14727 4052 computers - not counting the 4052's produced with -00 MAS boards.

I obtained my 4052 from an Arkansas medical school auction in 2000, so possibly the MAS board had been replaced since my 4052 has serial number B023898 - which should have had a -04 MAS board according to the list above.

 

[nikola-wan]

Jon,

I think you should start a new thread to continue the conversation on debugging your 4052 issue(s).

Jos' remake of the Diagnostic ROM pack has been very helpful so far in examining your 4052, but now I think we will have to do more digging into the hardware to find the SYSTEM ERROR culprit.

 

[nikola-wan]

DRP Long RAM test appears to behave oddly, same as before, 4 out of 7 times I ran it, I get a "DONE" no problem. 2 times the RAM test finished but instead of printing "DONE", the screen flashes and the test repeats. 1 time the RAM test finished, flashed the screen, and hung - in this case, the DRP LEDs indicated an unexpected IRQ from the ALU or I/O.

When the RAM test completed and printed "DONE", I ran the CRC test and was able to get a complete listing with matching CRCs except for ROMs past U893.
View attachment 1307862
Since it wasn't clear if there's a flaky DRAM anywhere despite testing every individual 4116, I pulled all the lower 32KB DRAMs that were a mix of Tektronix originals and newer chips, and put in all newer/tested DRAMs. The observed long RAM behaviors still persist where intermittently the DRP would repeat the test rather than complete with a "DONE" message. Also running the GPIB drive still returns a system error.

Actually your CRC test is not perfectly fine for the values for 805A and the following lines compared to Jos' v5.1 CRC in his first post in this thread. Your previous CRC picture had better CRCs for U805A and following.