TDS7404B ROM checksum failed - Error 4

[dodouelv]

Hi,
I have a TDS7404B Scope that doesn't startup proper. I stucks at the TEK-Software splash screen, while the Diagnostic LED on the PPC Board shows "4.". So Win XP starts as it should.
Reading the console output via the RS232 Connector on the PPC-Board I get the following output:

Code: [Select]

romPost: I am alive .


uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu


romPost: L2 cache turned on.

romPost: MPC107  Walking-one passed.

romPost: MPC107 configuration passed.

romPost: Intel21555 PCITOPCI bridge configuration passed.


romPost: PERFORMING ROM CHECKSUM TEST...


romPost: ROM checksum failed.

Expected Value: 0x0000E120
Actuall Value: 0x0000DF20
Setting the Dip-Switches (5 and 6) on the PPC to continue on failed POST, it boots and starts VxWorks to the point it tries to start the Acq Processor:

Code: [Select]


...

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 ]]]]]]]]]]]]]]]]]]]]]]]]]]]]]       Development System
 ]]]]]]]]]]]]]]]]]]]]]]]]]]]]
 ]]]]]]]]]]]]]]]]]]]]]]]]]]]       VxWorks version 5.3.1
 ]]]]]]]]]]]]]]]]]]]]]]]]]]       KERNEL: WIND version 2.5
 ]]]]]]]]]]]]]]]]]]]]]]]]]       Copyright Wind River Systems, Inc., 1984-1997

                               CPU: Tektronix HPP - IBM 750CXe.  Processor #0.
                              Memory Size: 0x2000000.  BSP version 2.0.1.10.
                             WDB: Ready.

done
KERNEL: THERMAL CONTROL INITIATED
Executing startup script c:/vxboot/topscript.hw ...
dbFsIoctl: invalid code 3
    ################### topScript starts ###############################


...



tcsLoadTableToNVRAM "pc:c:/vxBoot/setup.tcs"
value = 0 = 0x0
     updateAcqProcFirmware("dbfs:c:/vxBoot/acqProc.hex")
0x16987e0 (tShell): Program enable command didn't echo back properly.
logTask: 1 log messages lost.
value = 0 = 0x0
     cd "pc:"
value = 0 = 0x0

    raxInitializeDevices
done
0x16987e0 (tShell): (Re)starting Acq Processor
0x16987e0 (tShell): Acq processor powerup failure!

Executing the c:/vxboot/topscript.hw startup script also has a problem "dbFsIoctl: invalid code 3", don't know if this is relevant in any case.

The commonly known defective NV SRAM is working propably, anyway the config is OK and VxWorks starts.

Where is the "ROM" with the corrupted checksum is located and is it possible to replace and reprogram it?

I'm also concerned about the line of lower case "u"s at the beginning of the console listing. In all other outputs that I found, there where upper case "U" there. The difference between both characters is just 1 bit (Bit 5). Could this be related in an case to the checksum error? Bit 5 stucks on high on the bus or somthing similar.

In the past sometimes the scope doesn't start as well. After doing some vodoo power cycling and main power off/on switching it boots just fine without errors, but since it collects dust now for a view month, it dosen't start at all.

Has anyone any information that can help to get this thing working?

Many thanks in advance for your help
Dominik

[dodouelv]

Update:

Setting the Dip-Switches (5 and 6) on the PPC to continue on failed POST, it boots and starts VxWorks to the point it tries to start the Acq Processor:

The error when starting the Acq processor has been fixed. At some point while assembling the PPC, I stupidly bent a pin of the bus PCB connector, which eventually snapped off. That caused the error. A piece of wire soldered to the hole where the pin was located now does the job...

Now the oscilloscope boots up perfectly—at least it’s operational. However, I can’t tell whether the ROM checksum error affects the measurements.


Regards
Dominik

[coromonadalix]

if possible, do  run checks, spc  etc ... after 30 mins    if there are problems they may  pop out ...

[dodouelv]

if possible, do  run checks, spc  etc ... after 30 mins    if there are problems they may  pop out ...

All test results are normal. No errors shown.

In the past, sometimes the scope didn't start up properly. It would always get stuck on the splash screen before the relay on the AcqCard clicked.
If I had known about the error code LED back then—or even known that you could get a console output via RS232—I could say more about it. But I can imagine that even back then, it sometimes didn’t get past the ROM checksum test, and now it doesn’t get past it at all.

So the 1. question is: Where is that "ROM" located?  Maybe I can fix it by resoldering or cleaning contacts, if it is in a socket.

2. Question: What about the "U"/"u" line on the console output? Should there be upper case "U" or lower case "u"? Maybe that's a sign where to start diagnosing the board.


Dominik

[coromonadalix]

you ned to reed the big and lenghty tds 7k thread

there was cases of some eprom content corruption, you had to modify the startup script to repair it ...   for now i do not have access to the drive contining all my tds 7k archives,  thoses scripts are floating around


even some google search of : tds7k eeprom corruption repair script      will pop out the needed infos,   you could do a dump and it was possible to re-write it ...

from google ........


Step 1: Prepare the Scope (VxWorks Shell Access)

Before running any scripts, you must prevent the scope from booting into the standard TopScript application:
1. In Windows, navigate to C:\vxBoot\.
2. Locate the file named TopScript.hw and rename it to TopScript.tmp.
3. Connect a serial cable to the 10-pin IDC console port on the acquisition/processor board and open a serial terminal (9600 baud).
4. Reboot the oscilloscope. It will boot into the raw VxWorks prompt rather than launching the TekScope software.

Step 2: The EEPROM Dump Script

To check for corruption, first dump the exact contents of your EEPROM to a binary file. In the VxWorks terminal, change the directory to your local PC path and execute the following commands:
c
/* Navigate to the vxBoot directory */
cd "pc:c:/vxBoot"

/* Allocate memory buffer, read the EEPROM, and write to a file */
tempBuf = malloc(0x800)
nvMem_read(0, tempBuf, 0x800)
fdescriptor = open("dbfs:c:/vxBoot/eepromdump.bin", 0x0202, 0777)
bytesWritten = write(fdescriptor, tempBuf, 0x800)
close(fdescriptor)
Use code with caution.

Step 3: Repairing & Rewriting Corrupted Data

If your EEPROM data is corrupted (causing SPC errors, CRC issues, or failing the hardware scan), you can restore a healthy dump using a matching nvMem_write sequence.
1. Obtain a valid, uncorrupted .bin backup from an identical model or fix the CRC/header errors in your dumped eepromdump.bin using a hex editor.
2. Place the healthy binary file (e.g., eepromfix.bin) back into C:\vxBoot\.
3. Execute the restoration script via the VxWorks terminal:
c
/* Allocate buffer and open the fixed binary file */
tempBuf = malloc(0x800)
fdescriptor = open("dbfs:c:/vxBoot/eepromfix.bin", 0, 0)
bytesRead = read(fdescriptor, tempBuf, 0x800)
close(fdescriptor)

/* Write the valid data back to the EEPROM */
nvMem_write(0, tempBuf, 0x800)
Use code with caution.

Step 4: Restoring Normal Boot

Once the writing process completes successfully, restore the startup configuration in Windows:
1. Rename C:\vxBoot\TopScript.tmp back to TopScript.hw.
2. Reboot the oscilloscope to allow it to initialize normally.