Tektronix TDS 684C won't boot Front panel all LEDs Lit up only

[denimdragon]

And off we go again...

So during the last few days, I have been reducing my scope count. I'm currently working on a TDS 684C. When I first received the scope, it would not boot up and I set it aside. I would go back and try it again and see if I could get lucky and that never panned out for me. It would always come on with all the LEDs lit up with nothing on the screen.

Well today, I felt like getting down and dirty with it. I took it out of the cabinet to give it another good visual inspection, and still didn't see anything troubling. With the case off, I gave it a go again and it came on! Passed the start-up self test as well. So I turned it off to put the cabinet back on it and let it warm up so I could run SPC tests. Guess what, it went back to it's old ways again 

I have tried booting it with the #3 switch in the open position and still no boot. Initially all DIP switches were in the closed position. I can't remember the settings when I first recieved the scope. I've also tried plugging it into my external monitor (ASUS LCD), but that didn't work either. I'm not sure what to try next and I am looking for some advice.

I had a 694C, but I sold it when I found out how much the probes cost, so I would like to keep this one instead. I have a hacked DS1054Z for daily use and school but I still want a high BW scope in case I run into some projects that require it. From what I've read online, this one should be good until I can afford a newer high BW model. I'm also hoping I can add the 1M function to it once I get it working properly but I'm not sure if you can on this model.

Thanks in advance.

*It also has an optional hard drive. I'm not sure if that has anything to do with it or not.

Pardon the brightness on the one pictures...

[Jwalling]

When it doesn't boot, what's displayed on the seven segment LED?

[Armadillo]

Realm to the noisy world.
Hello, Noisy World!

[denimdragon]

When it doesn't boot, what's displayed on the seven segment LED?

GM Jay! When I saw that I had a reply a few minutes ago, I decided to turn the scope on again. Guess what, It boot! It must have known you were the one replying and you scared it into submission 

One thing stands out about this 684C and also a 544A I have that was doing the same exact thing. When I initially put them aside to work on them later, I stored them standing up with the front end pointing upwards. When I turned them on to check them again a couple of weeks later, they both worked.

Now earlier, this one wouldn't boot again, so I started the thread and made sure to store it front end up again until I received a reply. I had a hunch from reading on the Tek forum that someone else had a similar problem here https://forum.tek.com/viewtopic.php?t=138367  That's also where I read about the #3 dip switch, which didn't work. The OP of that thread changed out the display and the problem disappeared.

That got me to thinking that maybe the issue with this 684C is the same issue. I looked closer at the display after my attempts to boot it earlier and it looked like the CRT had a darker tinted blog under the top glass that receded after a minute or 2. Kind of like when you push an old calculator screen in with your finger and you could see the different colors until you took your finger off the screen and it reverts back to it's normal appearance. So now I'm wondering if the display is the culprit.

Right now the scope is still on with the cover off (strong fan blowing on it, I remembered  ) and I've let it warm up for about 30 minutes now. I was going to run SPC but I'm not sure if I should.

Here are the pics of the 7 seg and the scope:

[eKretz]

Go ahead and run it. It won't hurt anything. Have you checked the error log any of those times that you got it to boot?

[Jwalling]

Realm to the noisy world.
Hello, Noisy World!

?

Is it noon already?

[Jwalling]

If it boots, then there's not  much you can glean from the LED display. You have to catch it when it doesn't boot.

[denimdragon]

Go ahead and run it. It won't hurt anything. Have you checked the error log any of those times that you got it to boot?

Yes. But they are from 2007! I'm assuming it hasn't had any other errors and the initial error was a hard drive issue which was probably replaced. There is nothing recent on the log. That should be a good thing. I'm going to run SPC now. The scopes been on for quite a while because I didn't want to turn it off.

[denimdragon]

If it boots, then there's not  much you can glean from the LED display. You have to catch it when it doesn't boot.

I'm going to run the SPC and see what the results are. I'm curious. Do you think it could be the CRT?

[Jwalling]

Go ahead and run it. It won't hurt anything. Have you checked the error log any of those times that you got it to boot?

Yes. But they are are from 2007! I'm assuming it hasn't had and other errors and the initial error was a hard drive issue which was probably replaced. There is nothing recent on the log. That should be a good thing. I'm going to run SPC now. The scopes been on for quite a while because I didn't want to turn it off.

Now that I think about it, I have seen a TDS700C series scope with the HD option that would hang on the POST with a defective hard drive!

[denimdragon]

Go ahead and run it. It won't hurt anything. Have you checked the error log any of those times that you got it to boot?

Yes. But they are are from 2007! I'm assuming it hasn't had and other errors and the initial error was a hard drive issue which was probably replaced. There is nothing recent on the log. That should be a good thing. I'm going to run SPC now. The scopes been on for quite a while because I didn't want to turn it off.

Now that I think about it, I have seen a TDS700C series scope with the HD option that would hang on the POST with a defective hard drive!

That would be the Bee's Knees if the hard drive is the only issue! It passed SPC but I know it needs to be ran several times. It passed rather quickly relatively speaking (11:10). Also can't I set it up to test all the processes and loop it? I believe I read that somewhere and the only way to stop it is to turn it off.

Also how would I go about testing the HD? Thanks again for the help everyone!

OT - What is the difference in A,B,C,D Models. I assume the "D's" are Phosphorus.

[Armadillo]

Realm to the noisy world.
Hello, Noisy World!

?

Is it noon already?

OP was talking about 694 , 684 and going for higher BW, so if you cannot understand it, then you are not quite there yet, yeah!

There are many connectors, open it up and make sure all the connectors in particular the 2 vertical boards types are connected properly fully seated.
I would have a look at all the soldered joints and connectors joints for intermittent problems like this.
But the time keeper chip is also aging, I think already passed its time, could be a suspect. Swop one in if all else failed.

[Jwalling]

To eliminate the hard drive as a suspect, just remove the interconnect circuit board between the HD board and CPU. To test it, depends on what type of drive it is - PCMCIA or standard 2.5" PATA?

[denimdragon]

OP was talking about 694 , 684 and going for higher BW, so if you cannot understand it, then you are not quite there yet, yeah!

There are many connectors, open it up and make sure all the connectors in particular the 2 vertical boards types are connected properly fully seated.
I would have a look at all the soldered joints and connectors joints for intermittent problems like this.
But the time keeper chip is also aging, I think already passed its time, could be a suspect. Swop one in if all else failed.

LOL @ "Realm to the noisy world. Hello, Noisy World!"

I'm about to take the scope apart and inspect the boards but prior to that, I'm going to go with Jay's recommendation to see if it is , in fact, the HD causing the hangboot (new word ) issue. I finally had some good rest so I'm rarin' to go today (I'm a bit of an extremist when it comes to working with electronics and learning so 36-48 hour stints are the norm  ).

I also have some questions for you guys concerning this scope:

1. Is the memory upgradeable using the same process as used on the 7 series? Nevermind. I just found out that this model didn't have an option for more memory. That rained on my parade. Looks like I will be looking for a 784D or 794D.

2. Can I upgrade the HD to something larger (by conventional means) than it's current size? I think it's 2GB. Free space says 1.9GB? I'm contemplating on a SSD... yes I'm serious lol

3. How effective will the 520 schematic be as a reference for this C model?

4. Where to order the Dallas NVRAM Devices? I don't want something that's gonna die on me in 9 months like it did with TiN in his 7404 rebuild.

5. And lastly, does anyone have a working link to the Tektronix console build? I was looking yesterday but all the links were dead 


Ok, time to get after it! I will report back in a few...

*Is this ok to keep here since this repair will inevitably turn into a Frankenstein build thread, or should I make a new thread in "Projects" once this repair is done? Thanks again guys!

[denimdragon]

To eliminate the hard drive as a suspect, just remove the interconnect circuit board between the HD board and CPU. To test it, depends on what type of drive it is - PCMCIA or standard 2.5" PATA?

It's a standard 2.5" PATA. I have an 80GB 5400RPM Hitachi Travelstar. It would be cool to swap the 3.2GB out with that   

See Pics:

I was wondering about the formatting If I did use the Travelstar, but I think I saw something in the utilities for formatting the HD. I know it's there for floppy, but I'm not certain if it's there for the HD. Can anyone confirm? I'm putting it back together without the option board to see how it boots now.

[Jwalling]

2. Can I upgrade the HD to something larger (by conventional means) than it's current size? I think it's 2GB. Free space says 1.9GB? I'm contemplating on a SSD... yes I'm serious lol

3. How effective will the 520 schematic be as a reference for this C model?

4. Where to order the Dallas NVRAM Devices? I don't want something that's gonna die on me in 9 months like it did with TiN in his 7404 rebuild.

5. And lastly, does anyone have a working link to the Tektronix console build? I was looking yesterday but all the links were dead 


Ok, time to get after it! I will report back in a few...

*Is this ok to keep here since this repair will inevitably turn into a Frankenstein build thread, or should I make a new thread in "Projects" once this repair is done? Thanks again guys!

1. Right.

2. Don't bother. You'll never use up that much space! Older ones had 175MB PCMCIA, some flash based, some Viper rotating media drives. Even then you'd likely never get close to filling it.

3. Not really useful at all with regards to the ACQ board. The 600 series were completely different there.

4. Wouldn't worry about that either. Both have TWO batteries in them. On a dissected 20 year old one I have, one of the batteries is still @ 3.28V and the other is 2.97V
I suspect that the device switches over when is senses that the first battery falls below a certain threshold.
See picture where I've highlighted the 2 batteries on a DS1486.

5. The Tek console port adapter:  https://forum.tek.com/viewtopic.php?t=137307&start=20
When I made mine from that netlist, either power or GND was not getting to the board (can't remember which...)  One wire and I was up and running

[Jwalling]

Odd. The last time I measured the two batteries in March 2017, the one closest to pin 1 measured 3.01VDC, the one closest to Pin 16 measured 3.13VDC.
https://www.eevblog.com/forum/repair/tds-684c-nvram-backup/msg1173983/#msg1173983

Just double-checked them and they are definitely 3.28V and 2.97V. 

[denimdragon]

Well, I tried booting without the HD. No good. I checked all by voltages and everything was good. I also took a look at the front panel board and all I saw was a some flux remains around the 3 pins that connect the rotary encoders, but I also have a 744A dismantled and I look at the front panel encoders and they had  the same flux residue. Now that I think about, they came from the same source so they could have changed them out on both and did a shoddy job on this one. Initially, I just figured that was how the were from the factory.

I did see a solder joint at the base of one of the encoder legs that looked a tad suspicious, but I checked it's connection and it was good. I should have reflowed it but I have yet to solder on these PCBs, so I don't know their thermal characteristics. If this was a bad contact, would it cause the intermittent booting?

I'm kind of stuck now, and need some time to do a bit more research and think about it a bit more. I don't want to blindly start replacing components in hopes of "getting lucky", and worst, not knowing what the cause was/is and also risk upsetting the scopes balance. I've read that these scopes can act erratically if you do that.

Any suggestions at this point? 

[Jwalling]

The scope should boot fine if you disconnect the front panel board, although it will log the error. So I doubt that the front panel is the problem. What about the LED display?

[denimdragon]

The scope should boot fine if you disconnect the front panel board, although it will log the error. So I doubt that the front panel is the problem. What about the LED display?

I'm about to take a look at that. Between changing out the thermostat on my car, waiting for my little voltage reference to come in, and troubleshooting this scope, I'm about to go stir crazy    (Not to mention this 99° weather). Talk about a full days work. But the bad part is I'm having fun lol.

I'm also going to take a look at the display driver board. Something just isn't connecting right. Well at least that's what I think. I have another question. I'm assuming that the boot process checks all boards before the scope will fire up. Am I correct in assuming this?

[andy2000]

It's unlikely, but check the cal protection switch.  If it detects that it's in the unprotected position, the scope won't boot.  Also, if your NVRAM has been put in a socket make sure it's making good contact.

[denimdragon]

It's unlikely, but check the cal protection switch.  If it detects that it's in the unprotected position, the scope won't boot.  Also, if your NVRAM has been put in a socket make sure it's making good contact.

NVRAM is still in factory configurations. These scopes came from HP (old Compaq actually) so they are pretty much stock. The memory protect was the first thing I checked. I also checked the DIP switch to see if it could have failed open on me but it all looks good.

I ordered my kelvin wires for my Extech 380560 Milliohm meter and I'm hoping FedEx get's it to me soon. Trk info says it's out for delivery so my fingers are crossed. I want to use it to check for continuity. I strongly believe that something is just not connected properly or there is a cold joint somewhere. I'm consider throwing the boards in the oven to see if I can a bit of bit of reflow (I've confirmed some soldering state temps, but there's still a margin of error based on the many variables that exist). The couple of times it booted properly, the dang thing ran like it was brand new. 

You have any other trouble shooting ideas? Your help is greatly appreciated my friends.

I've actually started documenting these repairs in Excel spreadsheets. That's going to be a tremendous help in the future and from now on I'm logging all repairs I do. I have to take the scientific approach to this. The machines are just too complicated to not have logged data as an aid for these uncommon phantom issues.

[Jwalling]

The scope should boot fine if you disconnect the front panel board, although it will log the error. So I doubt that the front panel is the problem. What about the LED display?

I'm about to take a look at that. Between changing out the thermostat on my car, waiting for my little voltage reference to come in, and troubleshooting this scope, I'm about to go stir crazy    (Not to mention this 99° weather). Talk about a full days work. But the bad part is I'm having fun lol.

I'm also going to take a look at the display driver board. Something just isn't connecting right. Well at least that's what I think. I have another question. I'm assuming that the boot process checks all boards before the scope will fire up. Am I correct in assuming this?

Depending on how the dip switch #3 is set, yes. If off, it skips a lot of the testing. There is no test for the HV CRT driver board, though.

[denimdragon]

I'm just doing a visual inspection on everything and reconnecting connections. I'm hoping to see something out of the ordinary.

[denimdragon]

The scope should boot fine if you disconnect the front panel board, although it will log the error. So I doubt that the front panel is the problem. What about the LED display?

LED display was showing "_" then "8,6(?)" alternating.

[Jwalling]

The scope should boot fine if you disconnect the front panel board, although it will log the error. So I doubt that the front panel is the problem. What about the LED display?

LED display was showing "_" then "8,6(?)" alternating.

I think it may be useful to make a console port adapter.

[denimdragon]

I think it may be useful to make a console port adapter.

I've disassembled everything except for the PS and the CRT area for a thorough inspection under the microscope.

I plan on building the console in a little while. I did see this on the main level Trigger encoder while I was inspecting the front panel PCB. It's chipped right here.

[denimdragon]

So I took the scope down to it's bare bones before I build the console port for it to see if I noticed anything anywhere. I didn't see anything out of the order on the PS board, but I did see something on the shutter driver board. I used a 744A shutter driver board to compare since they both have matching part numbers save the last digit (-02 for 684C and -01 for 744). I'm assuming it's a rev. change but I can't see it being that different. Moving right along...

The 2 lead connector that connects the display driver board to the shutter driver board has one of the leads missing. It looks like it's been cut clean and the through hole that it would connect to looks clean like it wasn't ever used. I'm leaning toward it not being the issue unless it was vaporized? It doesn't make sense for it to be just dangling like that. I'm not sure what to think. Should I try and connect it before I put the scope back together? I'm not sure if it will botch something up. 

See pictures below:

[Jwalling]

So I took the scope down to it's bare bones before I build the console port for it to see if I noticed anything anywhere. I didn't see anything out of the order on the PS board, but I did see something on the shutter driver board. I used a 744A shutter driver board to compare since they both have matching part numbers save the last digit (-02 for 684C and -01 for 744). I'm assuming it's a rev. change but I can't see it being that different. Moving right along...

The 2 lead connector that connects the display driver board to the shutter driver board has one of the leads missing. It looks like it's been cut clean and the through hole that it would connect to looks clean like it wasn't ever used. I'm leaning toward it not being the issue unless it was vaporized? It doesn't make sense for it to be just dangling like that. I'm not sure what to think. Should I try and connect it before I put the scope back together? I'm not sure if it will botch something up. 

See pictures below:

Leave it alone. It came from the factory that way. As I said, the HV board is not the root cause of your scope hanging on boot.

[denimdragon]

Leave it alone. It came from the factory that way. As I said, the HV board is not the root cause of your scope hanging on boot.

  I just looked on eBay at another board with matching part numbers and saw that it was the same. Well I'll be putting it back together and making the console now I guess. (I'm a hard-headed pupil sometimes  )

[denimdragon]

5. The Tek console port adapter:  https://forum.tek.com/viewtopic.php?t=137307&start=20
When I made mine from that netlist, either power or GND was not getting to the board (can't remember which...)  One wire and I was up and running

The scope's display stays on the JAVA splash screen, but it does but up every time now that the adapter is connected.

I have a few questions about the console:

1. Unfortunately, this is all I'm getting on the console port. I'm using a DB9 to DB9 with USB adapter, and I have these pins connected: 2,3,7,8 and 9 is ground. Can anyone tell me what I have mixed up to fix the garble?

2. Are there any DIP switch settings I need to make or should they all stay in the closed position?

3. Is the Memory R/W switch on the right side set in the R/W position or off?

[denimdragon]

Ok so I finally have the console adapter working (RS232 got me initially). Here is the data:



RUNNING FROM DRAM.
DRAM test passed.


        Bootrom Header Checksum passed.
        Bootrom Total Checksum passed.
        BootRom Check Sum passed.
        Bus Error Timeout test passed.

Kernel Diagnostics Complete.

Calling SDM (monitor) Routine.

        Enabling Bus Control register. Value = 0x67
        IMR 1 Register test passed.
        Misc. Register test passed.
        Timer Interrupt test (Auto-Vector) passed.
        NVRam DSACK test passed.
        NVRam Write protected.
        Flashrom DSACK and JumpCode test passed.
        Flashrom Checksums passed.

Bootrom Diagnostics Complete.


DipSwitchValue: 0


Skipping boot loader.
Transferring control to FlashROM.

PCMCIA: option card with 1 controller detected at address 0x3000000
Checking for fixed  ATA Disk.
PCMCIA: Media Detected: 3255017472 Byte Disk
FLOPPY: Detected

Adding 5994 symbols for standalone.

#RESOURCES: MEMREQ=0x0: WAIT=1:
ld < hd0:/app/tdsrte1/logo.bin
value = 100483072 = 0x5fd4000
jplogosetup()

dlsym:error,symbol splashScreen not found in symbol space 100489392
value = 0 = 0x0

CPU: 68EC040.  Processor #0.
Memory Size: 0x1000000.  BSP version 1.0.

Executing Diagnostics
-> Start Power-On Diag Sequence
hwAccountant probe routines
  Probe for unexpected pending ints
  Dsp Instr mem size
  Dsp D2 mem size
  Dsp D1 mem size
  Dsy Vect0 mem size
  Dsy Vect1 mem size
  Dsy Wfm0 mem size
 +~+   Dsy Wfm1 mem size
 +~+   Dsy Text0 mem size
  Dsy Text1 mem size
  Acq number of digitizers
  Acq mem size
  Cpu timer interval uSec
  Cpu Dram size
  NvRam mem size
  Opt Math Package presence
  Opt RS232/ Cent presence
  Opt 1M presence
  Acq Intlv Cal Id presence
  Opt TvTrig presence
  Opt TvTrig index
  Dsy color presence
  Opt floppy drive presence
  Opt hard drive presence
  Acq limited bandwidth presence
  Acq number of user channels
dspForcedBus ................... pass
cpuDiagD2MiscReg ............... pass
cpuDiagDSPIntMaskReg ........... pass
cpuDiagDsyAccess ............... +~+  pass
dsp68kMemTest .................. pass
cpuDiagFIFOMem ................. pass
dspRunVerify ................... pass
dspBusRequestTest .............. pass
dspImplicitBusAccess ........... pass
dspTristarMemTest .............. pass
dsyRastModeV0Walk .............. +~+  pass
dsyRastModeV1Attrib ............ +~+  pass
dsyWaitClock ................... +~+  pass
cpuDiagAllInts ................. pass
nvLibrariansDiag ............... pass
calLibrarianDefaultCk .......... pass
checkIfCalFailed ............... pass
dspForcedBus ................... pass
acqProcThermistor .............. pass
digRegisterDiag ................ pass
digAcqMemDataDiag .............. pass
digAcqMemAddrDiag .............. pass
trigGtlRegisterDiag ............ pass
trigBtlRegisterDiag ............ pass
ch1EdgeTrigDiag ................ pass
lineTrigDiag ................... pass
dlyTrigDBTRunsAfter ............ pass
slewrateTrigDiag ............... pass
trigAttenSerialReg ............. pass
trigPreampSerialReg ............ pass
trigDTCSerialReg ............... pass
trigExtlSerialReg .............. pass
trigDacSerialReg ............... pass
TICountersDiag ................. pass
gtlBigCountersDiag ............. pass
trigBtlConfidenceDiag .......... pass
glitchTrigDiag ................. pass
pulseWidthDiag ................. pass
digRegisterDiag ................ pass
fpDiagConf ..................... pass
optDiagPM110Reg ................ pass
optDiagFloppyCacheMem .......... pass
optDiagFloppyControllerIO ...... pass
optDiagFloppyDrive ............. pass
optRS232DuartIO ................ UNTESTED
optRS232DuartIntLoop ........... UNTESTED
optCentronCntrlReg ............. UNTESTED
optTv8bitRegDiag ............... UNTESTED
optTvShiftRegDiag .............. UNTESTED
optTvXparentCodes .............. UNTESTED
optTvDontCareCodes ............. UNTESTED
optTvEdgeAndLevel .............. UNTESTED
optTvSyncLevels ................ UNTESTED
Executing Smalltalk
hwAccountant probe routines
  Probe for unexpected pending ints
  Dsp Instr mem size
  Dsp D2 mem size
  Dsp D1 mem size
  Dsy Vect0 mem size
  Dsy Vect1 mem size
  Dsy Wfm0 mem size
 +~+   Dsy Wfm1 mem size
 +~+   Dsy Text0 mem size
  Dsy Text1 mem size
  Acq number of digitizers
  Acq mem size
  Cpu timer interval uSec
  Cpu Dram size
  NvRam mem size
  Opt Math Package presence
  Opt RS232/ Cent presence
  Opt 1M presence
  Acq Intlv Cal Id presence
  Opt TvTrig presence
  Opt TvTrig index
  Dsy color presence
  Opt floppy drive presence
  Opt hard drive presence
  Acq limited bandwidth presence
  Acq number of user channels
can't open input 'fd0:/startup.bat'
  errno = 0x13 (S_errno_ENODEV)
taskSpawn ("javastart",200,0x0,40000,sysExecScript,"hd0:/app/tdsrte1/RTE1.BAT")
value = 100239728 = 0x5f98970

Smalltalk/V Sun Version 1.12
Copyright (C) 1990 Object Technology International Inc.
# TDS RTE1.1 startup file.
nulldev = open("/null",3,0666)
new symbol "nulldev" added to symbol table.
nulldev = 0x5f8ff10: value = 5 = 0x5
taskSpawn "Redirect",250,0,0x4000,ioGlobalStdSet,1,nulldev
value = 100203852 = 0x5f8fd4c

ld < hd0:/app/tdsrte1/java68k.o
0x5f7f13c (sysScriptExec): Apps General Purpose Event Queue not registered in this system
0x5f7f13c (sysScriptExec): Apps Variable Event Queue not registered in this system

[Jwalling]

Ok so I finally have the console adapter working (RS232 got me initially). Here is the data:


SNIP

1. Did it hang on that particular boot? It doesn't look like it...
2. What firmware revision does your scope have?

Odd are those extra characters "+~+" before some of the tests that are related to the CPU board display areas.

Attached is a boot log from a good TDS684C with no hard drive. Firmware revision is 5.1e. Yours will be somewhat different since you have the hard drive. I would disconnect it for now and then you can compare it better with my boot log.

[denimdragon]

1. Did it hang on that particular boot? It doesn't look like it...
2. What firmware revision does your scope have?

Odd are those extra characters "+~+" before some of the tests that are related to the CPU board display areas.

Attached is a boot log from a good TDS684C with no hard drive. Firmware revision is 5.1e. Yours will be somewhat different since you have the hard drive. I would disconnect it for now and then you can compare it better with my boot log.

It hung earlier on the splash screen because I had My Rx, Tx incorrect. It hasn't hung since. The firmware is 5.1e, and I did disconnect the hard drive. Here is the log comparison and the only differences I see are the "+~+" before certain lines. I'll have to find out what that means. Also it says that my DUART I/O is untested. What does that mean?

[chihaxinh]

Hi denimdragon

How to grab boot log in Tektronix . Can you write basic step to step , i'm have one tds 520b can't boot and display green screen only when bootting ( i using external display - my display board fault )

Thank you so much !

Nam Nguyen Hai

[denimdragon]

Hi denimdragon

How to grab boot log in Tektronix . Can you write basic step to step , i'm have one tds 520b can't boot and display green screen only when bootting ( i using external display - my display board fault )

Thank you so much !

Nam Nguyen Hai

Have you built the console port adapter yet?

[Jwalling]

1. Did it hang on that particular boot? It doesn't look like it...
2. What firmware revision does your scope have?

Odd are those extra characters "+~+" before some of the tests that are related to the CPU board display areas.

Attached is a boot log from a good TDS684C with no hard drive. Firmware revision is 5.1e. Yours will be somewhat different since you have the hard drive. I would disconnect it for now and then you can compare it better with my boot log.

It hung earlier on the splash screen because I had My Rx, Tx incorrect. It hasn't hung since. The firmware is 5.1e, and I did disconnect the hard drive. Here is the log comparison and the only differences I see are the "+~+" before certain lines. I'll have to find out what that means. Also it says that my DUART I/O is untested. What does that mean?

How is the dip switch set? On mine, all switches are set to on. If switch 3 is off, it'll skip some tests.
you won't be able to glean any useful info from the console port till you get it to hang.

[denimdragon]

How is the dip switch set? On mine, all switches are set to on. If switch 3 is off, it'll skip some tests.
you won't be able to glean any useful info from the console port till you get it to hang.

Oh ok. I need it to hang. Also all dip switches are set to on. I'll see if I can get it to hang again 

[chihaxinh]

Have you built the console port adapter yet?

Hi Denimdragon

Sorry for Off Topic , but i dont know schematics or diagrams to build TDS Console Port, All topic in tek forum have change url and die . If you know how to build console adapter port pls guide me .

Thank you so much !
Nam Nguyen Hai

[Jwalling]

Hi Denimdragon

Sorry for Off Topic , but i dont know schematics or diagrams to build TDS Console Port, All topic in tek forum have change url and die . If you know how to build console adapter port pls guide me .

Thank you so much !
Nam Nguyen Hai

Link is in this very thread!

[denimdragon]

Have you built the console port adapter yet?

Hi Denimdragon

Sorry for Off Topic , but i dont know schematics or diagrams to build TDS Console Port, All topic in tek forum have change url and die . If you know how to build console adapter port pls guide me .

Thank you so much !
Nam Nguyen Hai

Hi Denimdragon

Sorry for Off Topic , but i dont know schematics or diagrams to build TDS Console Port, All topic in tek forum have change url and die . If you know how to build console adapter port pls guide me .

Thank you so much !
Nam Nguyen Hai

Link is in this very thread!

"5. The Tek console port adapter:  https://forum.tek.com/viewtopic.php?t=137307&start=20
When I made mine from that netlist, either power or GND was not getting to the board (can't remember which...)  One wire and I was up and running"

There you go 

[Armadillo]

Have you built the console port adapter yet?

Hi Denimdragon

Sorry for Off Topic , but i dont know schematics or diagrams to build TDS Console Port, All topic in tek forum have change url and die . If you know how to build console adapter port pls guide me .

Thank you so much !
Nam Nguyen Hai

Option 13 refers to the RS232 centronic board at the back of the TDS unit.

The objective is to connect this board to the A11 processor board J40. [by jumper wires or by pcb adapters]

On the TDS520, the console port is J40, a PCB edge connector 10 X 2 [See pictures].

The correct pinout is as follows;


Console port - Option 13 Board - (Signal Name)
A10 - 1 - (D24)
B10 - 3 - (D25)
A9 - 5 - (D26)
B9 - 7 - (D27)
B8 - 2 - (D28)
A7 - 4 - (D29)
B7 - 6 - (D30)
A6 - 8 - (D31)

B1 - 21 - (A1)
A1 - 23 - (A2)
B2 - 25 - (A3)
A2 - 22 - (A4)
+5V (B6) - 24 - (A5)
GND (A3/A8) - 26 - (A6)

B5 - 12 - (INT#)
B4 - 15 - (IOCS#)
A5 - 16 - (SYSRESET#)
A4 - 17 - (RNW)

A3, A8 - 9, 13, 19 - (GND)
B6 - 10, 20 - (+5V)

B3 - not connected

not connected - 11 - (DS#)
not connected - 14 - (DSACK0#)
not connected - 18 - (AS#)

Notes:
On the console port "B" is the top side of the processor board.
Signals A5 (Pin 24) and A6 (Pin 26) need to be set to +5V and Gnd to make sure the serial port of the option 13 board is selected.
The 3 ground pins (9, 13, 19) should be connected on the option 13 board, so normally you only need to connect one of these to the console port connector.
The 2 +5V pins (10, 20) should be connected on the option 13 board, so normally you only need to connect one of these to the console port connector.

This link below provides exact information from the contributors there. Also PCB adapter board designed by someone.

Take a look; https://forum.tek.com/viewtopic.php?t=137307&start=20

I hope this compile give you a proper direction/starter to building the console service adapter.

[denimdragon]

I finally got it to hang!!! And now it's consistent. Maybe the bad weather here scared the heck out of it  Here's what I got in my console:

{\xf4}{EOF}{GS}

And that's it. Anyone know what this means? Thanks.

[Jwalling]

I finally got it to hang!!! And now it's consistent. Maybe the bad weather here scared the heck out of it  Here's what I got in my console:

{\xf4}{EOF}{GS}

And that's it. Anyone know what this means? Thanks.

Never seen that before. Must be failing very early in init. Could be the bootrom or some sort or I/O failure.
I would start by checking the address and data lines to the EEPROM which holds the boot code.

[Armadillo]

Firstly, I think you should check proper & complete Reset timing Circuit;

On the 520 CM schematic, it would be the U1175;

[denimdragon]

Firstly, I think you should check proper & complete Reset timing Circuit;

On the 520 CM schematic, it would be the U1175;

I believe I've located that area. It's a tantalum cap on this board it appears. How do I check it @Armadillo 

[Armadillo]

I suggest you confirm that "Power-on reset asserts for a minimum of 400 milliseconds after the +5 V supply stabilizes." is available and stable, clean, no glitches right into the reset pin of the processor and also;
tweezers out the tantalum and the MLCC and check ESR and capacitance.

Edit: BTW, I don't like MLCC though it look innocent.
Edit: bear in mind that this is a case of intermittence problem, so you will be looking at marginally out of spec components and trial and errors will be unavoidable.   

Edit: Also the LED readout would provide some infomation;
Edit: Also check the console hook up is not shorted.

[denimdragon]

How often tant caps go bad?

[Armadillo]

How often tant caps go bad?

Not often, the thing mostly fail short, at times moisture creepage or crack, but it always where the small percentage that creates the most problems. How much are engineers certain on certainty and probability? MTTF, MTBF are all mathematical statistics. 
Well, it would be prudent to go through the obvious troubleshooting steps and iron out along the way.

Not often I would say, but you will still need to unearth this 400ms burden and move forward unless the LED is showing some status of life.

[denimdragon]

Not often, the thing mostly fail short, at times moisture creepage or crack, but it always where the small percentage that creates the most problems. How much are engineers certain on certainty and probability? MTTF, MTBF are all mathematical statistics. 
Well, it would be prudent to go through the obvious troubleshooting steps and iron out along the way.

Not often I would say, but you will still need to unearth this 400ms burden and move forward unless the LED is showing some status of life.

Ok, where do I check the 400 ms Signal? On the 7705 IC? The RS232 IC or the DUART IC? I'm confused. I'm guessing the 7705 (U1175).

[Armadillo]

" is available and stable, clean, no glitches right into the reset pin of the processor a

[denimdragon]

Never seen that before. Must be failing very early in init. Could be the bootrom or some sort or I/O failure.
I would start by checking the address and data lines to the EEPROM which holds the boot code.

These doesn't have the long EEPROM like the older models. I think it's the square type. I only see two ICs with the typed numbers on the A11 one is 163-1112-00 and the other is 163-0693-00.

" is available and stable, clean, no glitches right into the reset pin of the processor a

This board doesn't appear to have the same processor. For sure, it's in a different location than my 744A A11 board.

[Armadillo]

This board doesn't appear to have the same processor. For sure, it's in a different location than my 744A A11 board.

Don't it have a Q3 collector?

[denimdragon]

Don't it have a Q3 collector?

Ah Haa. I thought I might be on the right path. I'll check there soon as I get home 

Pardon my ignorance.  This is the first time I've had to troubleshoot this indepthly. I'm learning a lot as I go and I really appreciate all the help guys.

[denimdragon]

I got it going again. It appears by console port building wasn't as rock solid as I thought. I had to touch up one wire that wiggled loose. I ran the "i" command once I got it going. Does any of this look familiar?

-> i


  NAME        ENTRY       TID    PRI   STATUS      PC       SP     ERRNO  DELAY

---------- ------------ -------- --- ---------- -------- -------- ------- -----

tExcTask   _excTask      5ffca24   0 PEND        50575ec  5ffc98c       0     0

tLogTask   _logTask      5ffa124   0 PEND        50575ec  5ffa088       0     0

tShell     _shell        5ff6540   1 READY       50297fc  5ff6208       0     0

gpibIHTask _gpibIHTask   5fe8c50   4 PEND        50575ec  5fe8bd0       0     0

fifoTask   _fifoTask     5ffe020   9 READY       502547c  5ffdfd4       0     0

causeEnable_causeEnable  5fffcd0  10 PEND        50575ec  5fffc40       0     0

rtcTicker  _dateTimeQue  5feca04  51 DELAY       501ac22  5fec9b8       0    44

priority_no_priority_no  5fe9fb4  60 PEND        502547c  5fe9f70       0     0

grun Reboot_rebootGrun   5fe45fc  65 PEND        502547c  5fe45b4       0     0

GPIB monito_GpibMonitor  5fe82f0  68 PEND        502547c  5fe8288       0     0

GPIB reboot52032cc       5fe79b0  68 PEND        502547c  5fe7960       0     0

trigStatus _trigStatusQ  5fed3a0  69 DELAY       501ac22  5fed360       0     8

GPIB parser_Grun         5fe7070  70 PEND        502547c  5fe6cec  3d0001     0

V main     _main         5ff2fc4 100 PEND        502547c  5ff2f28  3d0002     0

calThread3 _calRunner    5fff2fc 102 PEND        502547c  5fff2bc       0     0

calThread2 _calRunner    5ff0724 102 PEND        502547c  5ff06e4       0     0

calThread1 _calRunner    5fef5f8 102 PEND        502547c  5fef5b8       0     0

calThread0 _calRunner    5fee4cc 102 PEND        502547c  5fee48c       0     0

evalProcess_eval_loop    5feb6a0 120 PEND        502547c  5feb660  3d0002     0

value = 0 = 0x0

-> scopeErrorLogDumpToConsole

Scope Error Log Contents:
 WED APR 04 15:22:59 2007  ERROR: 250 mass storage error, READ_FAIL [46,0,28,0,1,2,12,1b,ff]-> [40,20,20,28,0,3,2]
TUE APR 10 18:11:37 2007  ERROR: 250 mass storage error, READ_FAIL [46,4,0,1,1,2,12,1b,ff]-> [44,20,20,0,1,11,2]
TUE APR 10 18:14:08 2007  ERROR: 250 mass storage error, FORMAT_FAIL [4d,4,2,12,6c,f6]-> [44,0,0,f6,2,1,2]
value = 0 = 0x0

->

[Armadillo]

But the time keeper chip is also aging, I think already passed its time, could be a suspect. Swop one in if all else failed.

Ehm!, time keeper was my initial suspect [I reckon batt low to coup with the comm speed for calibration].

[denimdragon]

But the time keeper chip is also aging, I think already passed its time, could be a suspect. Swop one in if all else failed.

Ehm!, time keeper was my initial suspect [I reckon batt low to coup with the comm speed for calibration].

You mean the 2007 log entries? Also this 684C has a HD. I think it might have been replaced when Compaq computers owned it and the log was never cleared.

@Jwalling - I also tried to reconnect the HD board and when I did, the 7 segment went crazy on me. I unplugged the board and it booted fine with the console port attached. I'm still at square one but at least I can talk to the scope again.

I also ran SPC again, and once again, the scope passed with no issues. This scope is great when it boots properly. I have to figure this out. I have til the 11th before school starts, thanks to Harvey (one good thing came out of it). I'm hoping I can get it going by then.

[denimdragon]

I also have something else I need to understand if anyone knows. Why does the scope boot consistently when the console port is attached but won't but boots rarely when the serpar board (RS232) is attached. My simple logic makes me think that the serpar board is the issue unless I'm missing something 

[Jwalling]

I also have something else I need to understand if anyone knows. Why does the scope boot consistently when the console port is attached but won't but boots rarely when the serpar board (RS232) is attached. My simple logic makes me think that the serpar board is the issue unless I'm missing something 

If it always boots with the serial/parallel port board disconnected, I'd just leave it disconnected. Do you really need that interface?

[denimdragon]

If it always boots with the serial/parallel port board disconnected, I'd just leave it disconnected. Do you really need that interface?

I think that's what I'll end up doing, but I'll have to keep the console port adapter plugged in and keep it attached to one of my computers with serial console running. That's the only way it functions properly. Over time as I learn more, I will fix it little by little. And I can learn more about the code side of these machines.

Last concern, running it like this won't be an issue as long as it passes calibration and SPC right? If not, I'm going to start putting it back together and setting it up in it's own little area. I need to get started on changing the relays on the 744A anyways as I can learn more because that scopes component layout is closer to the 520 schematic. That's another thread.

Thanks everybody for the help and as I figure out the problem, I will post back here. I have some consistency now at least 

[Jwalling]

I think that's what I'll end up doing, but I'll have to keep the console port adapter plugged in and keep it attached to one of my computers with serial console running. That's the only way it functions properly.

 

So you're saying all these conditions must be met before the scope will always boot?:
1. Option 13 must be disconnected.
2. Console port must be connected.
3. The console port must be connected to a PC.
4. The PC must be running a terminal program.

[denimdragon]

 

So you're saying all these conditions must be met before the scope will always boot?:
1. Option 13 must be disconnected.
2. Console port must be connected.
3. The console port must be connected to a PC.
4. The PC must be running a terminal program.

Yes sir. I also just found out that my large selection knob is non-functional. I wonder if this is the culprit?

[denimdragon]

Ok, so I reseated the bus board that connects the options board to A11. I boots up now, but gets hung on the JAVA splash screen.

1. Serial Console port is not open on laptop
2. Scope is still connected to laptop
3. Just opened serial console on my laptop and scope boots up from splash screen

So now:

1. Console port must be connected.
2. The console port must be connected to a PC.
3. The PC must be running a terminal program.

I'm also getting the weird "+~+" again. It did show this with the hard drive disconnected:


CMCIA: option card with 1 controller detected at address 0x3000000

Checking for fixed  ATA Disk.

PCMCIA: Media Detected: 3255017472 Byte Disk

FLOPPY: Detected


Adding 5994 symbols for standalone.


#RESOURCES: MEMREQ=0x0: WAIT=1:

ld < hd0:/app/tdsrte1/logo.bin

value = 100483072 = 0x5fd4000

jplogosetup()


dlsym:error,symbol splashScreen not found in symbol space 100489392

value = 0 = 0x0


CPU: 68EC040.  Processor #0.

Memory Size: 0x1000000.  BSP version 1.0.


Executing Diagnostics

-> e
 +~+   Dsy Wfm1 mem size
 +~+   Dsy Text0 mem size
  Dsy Text1 mem size
  Acq number of digitizers
  Acq mem size
  Cpu timer interval uSec
  Cpu Dram size
  NvRam mem size
  Opt Math Package presence
  Opt RS232/ Cent presence
  Opt 1M presence
  Acq Intlv Cal Id presence
  Opt TvTrig presence
  Opt TvTrig index
  Dsy color presence
  Opt floppy drive presence
  Opt hard drive presence
  Acq limited bandwidth presence
  Acq number of user channels
dspForcedBus ................... pass
cpuDiagD2MiscReg ............... pass
cpuDiagDSPIntMaskReg ........... pass
cpuDiagDsyAccess ............... +~+  pass
dsp68kMemTest .................. pass
cpuDiagFIFOMem ................. pass
dspRunVerify ................... pass
dspBusRequestTest .............. pass
dspImplicitBusAccess ........... pass
dspTristarMemTest .............. pass
dsyRastModeV0Walk .............. +~+  pass
dsyRastModeV1Attrib ............ +~+  pass
dsyWaitClock ................... +~+  pass
cpuDiagAllInts ................. pass
nvLibrariansDiag ............... pass
calLibrarianDefaultCk .......... pass
checkIfCalFailed ............... pass
dspForcedBus ................... pass
acqProcThermistor .............. pass
digRegisterDiag ................ pass
digAcqMemDataDiag .............. pass
digAcqMemAddrDiag .............. pass
trigGtlRegisterDiag ............ pass
trigBtlRegisterDiag ............ pass
ch1EdgeTrigDiag ................ pass
lineTrigDiag ................... pass
dlyTrigDBTRunsAfter ............ pass
slewrateTrigDiag ............... pass
trigAttenSerialReg ............. pass
trigPreampSerialReg ............ pass
trigDTCSerialReg ............... pass
trigExtlSerialReg .............. pass
trigDacSerialReg ............... pass
TICountersDiag ................. pass
gtlBigCountersDiag ............. pass
trigBtlConfidenceDiag .......... pass
glitchTrigDiag ................. pass
pulseWidthDiag ................. pass
digRegisterDiag ................ pass
fpDiagConf ..................... pass
optDiagPM110Reg ................ pass
optDiagFloppyCacheMem .......... pass
optDiagFloppyControllerIO ...... pass
optDiagFloppyDrive ............. pass
optRS232DuartIO ................ UNTESTED
optRS232DuartIntLoop ........... UNTESTED
optCentronCntrlReg ............. UNTESTED
optTv8bitRegDiag ............... UNTESTED
optTvShiftRegDiag .............. UNTESTED
optTvXparentCodes .............. UNTESTED
optTvDontCareCodes ............. UNTESTED
optTvEdgeAndLevel .............. UNTESTED
optTvSyncLevels ................ UNTESTED
Executing Smalltalk

hwAccountant probe routines
  Probe for unexpected pending ints
  Dsp Instr mem size
  Dsp D2 mem size
  Dsp D1 mem size
  Dsy Vect0 mem size
  Dsy Vect1 mem size
  Dsy Wfm0 mem size
 +~+   Dsy Wfm1 mem size
 +~+   Dsy Text0 mem size
  Dsy Text1 mem size
  Acq number of digitizers
  Acq mem size
  Cpu timer interval uSec
  Cpu Dram size
  NvRam mem size
  Opt Math Package presence
  Opt RS232/ Cent presence
  Opt 1M presence
  Acq Intlv Cal Id presence
  Opt TvTrig presence
  Opt TvTrig index
  Dsy color presence
  Opt floppy drive presence
  Opt hard drive presence
  Acq limited bandwidth presence
  Acq number of user channels
can't open input 'fd0:/startup.bat'

  errno = 0x13 (S_errno_ENODEV)

taskSpawn ("javastart",200,0x0,40000,sysExecScript,"hd0:/app/tdsrte1/RTE1.BAT")

value = 100239728 = 0x5f98970



Smalltalk/V Sun Version 1.12

Copyright (C) 1990 Object Technology International Inc.

# TDS RTE1.1 startup file.

nulldev = open("/null",3,0666)

new symbol "nulldev" added to symbol table.

nulldev = 0x5f8ff10: value = 5 = 0x5

taskSpawn "Redirect",250,0,0x4000,ioGlobalStdSet,1,nulldev

value = 100203852 = 0x5f8fd4c


ld < hd0:/app/tdsrte1/java68k.o

0x5f7f13c (sysScriptExec): Apps General Purpose Event Queue not registered in this system

0x5f7f13c (sysScriptExec): Apps Variable Event Queue not registered in this system

[denimdragon]

And why in the world can't I find the User Manual for the 684C? All I'm trying to figure out is if I can use these LeCroy PP006A with it (500MHz, Passive, 12pF). I believe I can but I want to make sure because Lecroy is a bit foreign to me right now. I guess I could look up the probes compensation range. It's only 2pF difference but, I like to be certain (which usually gets me going down a rabbit hole  ).

*Also probe compensation fails on the LeCroy probe, which is understandable, but it also fails on my P6139A Tek probe.

[Jwalling]

 

So you're saying all these conditions must be met before the scope will always boot?:
1. Option 13 must be disconnected.
2. Console port must be connected.
3. The console port must be connected to a PC.
4. The PC must be running a terminal program.

Yes sir.

That is really strange. Only thing I can think of guess is that when the console port is connected, it might slow down the boot process.

I also just found out that my large selection knob is non-functional. I wonder if this is the culprit?

No.

[andy2000]

 

So you're saying all these conditions must be met before the scope will always boot?:
1. Option 13 must be disconnected.
2. Console port must be connected.
3. The console port must be connected to a PC.
4. The PC must be running a terminal program.

Yes sir. I also just found out that my large selection knob is non-functional. I wonder if this is the culprit?

That implies the scope is waiting for some kind of response from the terminal at some point in the boot process.  What if you monitor the output of the console port without connecting the scope's RX pin?  You might be able to see precisely where it hangs. 

I'd also look for problems around the console port and it's associated parts.  Maybe there's a missing, or bad pull up resistor, or some other odd problem.

A problem with the knob wouldn't cause it to not boot, but it might have a common cause.

[Jwalling]

The scope should boot fine if you disconnect the front panel board, although it will log the error. So I doubt that the front panel is the problem. What about the LED display?

LED display was showing "_" then "8,6(?)" alternating.

Going through this thread again after some 5 years or so. Since then, I have seen that exact failure a few times - each time I saw that alternating 6,8 pattern, it was a bad DS1486. Replacing it corrected the problem.