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My name is Francisco. Thank you for allowing to be a member of the forum.
I have two oscilloscopes that work very well, without errors. TDS 524A / TDS 754D.
I want to change the nvrams for security, before your batteries are used up. I need help to save the files of the nvrams.
Is it possible to pass the files to a diskette, put the new nvrams and transfer the files from the diskette to the nvrams, using the floppy disk drives of the oscilloscopes?
In what state will the oscilloscopes be, if the batteries are used up and I do not arrive in time to change the nvrams?
there are at least three ways to transfer the contents of the NVram. download the images using a GPIB cable and the program tektool or tekfwtool. the second way is to convert your option 13 card (parallel/serial) to a debug port and write the image out using the console debug commands. The third and riskiskest is to desolder the Nvram and put it in a rom/eprom reader/writer and extract the data with whatever tool the programmer comes with. The first two methods are discussed in this forum in various places.
If your 524 NVram goes bad, then you will lose your calibration and the scope will need to calibrated after the new NVram is installed. The 754D calibration is on the acq board in a totally different non-battery nvram. In eiter case, if the boot routine fails to prokperly read/write to the NVram, then it will fail.
If your NVram fails before you get the image off, I can send you an image that will allow it to properly boot, but calibration (especially high freq amplitude) may be off, because these values are set during calibration and are unique to each machine.
If it works on a 700c series, it should work on anything in the 500/600/700 family as the memory locations all point to 04000000.
The older 500/600A series only use 512K (DS1650 or DS1250). The 700 and all B and later series use a DS1486 with 128K with the DS1650 starting at 04080000 and the same 512k length.
thus, anything that records 04000000 and is 1024K long should do the job for any of the family. I usually use tektool and record starting at 04000000 with a length of fffff.
I'll be able to test the software in a week or so and confirm here, unless someone else does it first...
Shouldn't be a problem for you to wait until then, as we can always write to a new chip and put it in. I strongly recommend putting in a socket (simple, not the one with round pin holes).
on the 754D, it has two NVram chips (DS1486 and DS1650/1250). The 524A only has one NVram, the DS1650. Thus, the 524A only has a size of 512K , while the 754D has a 128K and the 512K. The DS1486 starts at the normal 04000000 in the 754D (as does the DS1650 in the 524A). However, the DS1650 does not start at the 128K boundary, but at 04080000 (hex) in the machine.
So, in either case, reading and writing back from 04000000 for a length of A0000 will cover both chips and get the job done. If the chips are to be written to with a rom burner, then the DS1486 gets the important information starting at 04000000. The DS1650 is just for overflow, but the info starts at 04080000 for 512k bytes. (80000 hex)
I was able to evaluate the tds754D today. The program does record the Nvram properly. It also writes back that NVram, except that any options that have been enabled beyond what TEK put in seem to disappear.
What I did:
formatted a floppy with the 754d
used the dump program to dump the nvram
compared the file with a dump using tektool - differences in two zones. 0-8 (totally normal as this is the clock data)
also had 4 words different at 0Cxx - not typical of an immediate tektool read
Then, using tektool, wrote an old NVram (prior to calibration and addition of extra options) to the scope
booted scope - options as before cal and traces were offset from null (i.e. would need a SPC to fix), otherwise, fine.
renamed the dump file to writedmp as directed and put write programs on newly formatted disk
booted scope with floppy inserted - program ran as advertised.
On reboot, lost extra options. scope did a long self test vice the short that usually occurs
on first try, got Processor error that cleared after reboot.
on second try with above process, got a good boot with the floppy write process and no memory error. Had same differences in file after dumping using tektool.
Analysis: program works to copy and reestablish NVram, but will probably remove any options not set by TEK. Thus, if you think your options were set at the factory or an upgrade, this is a fine program. So, look at the options (excluding option 13 and 1F) and see if you can live without them.
Cause: I think that there may be a time stamp that gets properly set with using tektool, but not with the disk write. This causes the scope to do a full test and it might refer to a secondary source of what options are installed. seeing differences, the scope removes the extra added options. As I stated above, a dump and read using tektool results in the low 3-4 words (xxx0-xxx8) being different, but this program has low and high different.
I'll try to do the 524 later this week, as I'm still moving a little slow, but I suspect the results will be the same.
I understand that that means that with the read and write diskettes, I can do a dump without losing the configuration and factory calibration.
I do not have the possibility to copy and save the calibration in nvram in another way, I can only do it with these programs. I can not modify anything else. I do not have the means nor do I know them.
I await your approval to do so with the discs in TDS 754D.
I will do it on TDS 524A only when you do the test.
Thanks Strikc, thank you sincerely.
Analysis: the program works to copy and restore NVram, but will probably eliminate any option that has not been established by TEK. Therefore, if you believe that your options were set at the factory or an update, this is a good program. So, look at the options (excluding options 13 and 1F) and see if you can live without them.
What are options 13 and 1F for?
The calibration is not lost and the boot will start without errors?
I didn't mean to be confusing. The 754D calibration is on the ACQ board in separate NVram (no battery). So, you will not lose the calibration using these disks - both for backup and restore. If the NVram battery fails, then the scope will lose some constants and may or may not boot properly.
the 524A is different. The calibration IS contained in the NVram, so battery failure will cause loss of calibration and the scope may not boot.
I don't know yet if the restore program functions as well with it as the 754D.
I recommend you go ahead and back up the 754D with the main (larger) program and back up the 524A with the smaller program. At that point you might think about making a debug port. Your 754D should probably have an option 13 card (serial and parallel). Unless you really have been using a serial or parallel port, this option is pretty useless and converting it would allow you to do many things, including backing up and restoring nvram.
Option 13 is the parallel/serial port in the back (if so equipped)
Option 1F is the floppy drive
Both of these options are enabled through the hardware, not the NVram. Things like 1M (large memory) and 2F (fast fouier transform) are enabled in the NVram in both of your scopes.
Options can always be restored wih a gpib hookup or the debug port once you have new NVrams.
It is understood. I thought about buying the tl86 professional mini programmer to copy nvram. Your tests say that it is not necessary.
I'll tell you what I've done:
Backup of the great reading program TDS 754D on disk
Backup of the small TDS 524A reader on another disk
Backup (name changed) large write program TDS 754D on another disk
Backup (name changed) small scan program TDS 524A on another disk.
I need your advice.
If the batteries fail and the computers do not start, now there should be no problems. I just have to put nvram and dump the corresponding writing disc.
Put now or wait for a failure?
Knee isn't doing well right now, but hope remains.
If you have a good desoldering tool, then you could order a couple of 1486s and three 1650s off greedbay. These come from China and take a few weeks to get to you. Once the chips arrive, you can carefully desolder the nvram and put in a socket. I recommend an extra chip as occasionally they won't hold an image.
Generally speaking, the old nvram will still work if you don't over heat them. At that point, you can put in the new chips and attempt to write to them.
If the disk write fails, you could copy the old chips or simply burn using the dump files. Having the dump is the big deal.
I'm sure your knee will be fine. The problem is that it is not a quick recovery, I know from experience. You have to rehabilitate yourself with medical indications, you'll be fine, I'm sure.
The nvram comes from this Ebay seller: chipsgate
Will they serve?
Only 4 will arrive, I did not request 1 replacement.
I have not thought about the possibility nvram defective as you say.
It's doing a little better.
No, only the 700a series and later or the 500b series can be modified.
The 744/54a b or c can be upgraded to a 784. The 540c or d can be upgraded to a 580.
The straight 744 has the capability to be calibrated to close to 1ghz, but will not upgrade to 4gs/sec.
The 500a (and non a) series has different attenuators and connection method than the later scopes. No way to get the pig to sing. They are truly 500mhz scopes.
The 520/4 only has two full memory channels that can be combined to get the 500 ms/sec acq rate. The 540/4 has four full channels that can combine to 1gs/sec.
The 700 and 500b up have double the acq rate, but tek limited the combining the channels to two in the 500 series. Thus, a max acq rate of 2Gs/sec in a 540b and up, but a 4gs/sec in the 700a an up.
Hopes this helps.
The tissues of your leg have suffered an important aggression to receive your new knee. It is necessary to wait until the inflammation recedes. It is a good indicator to be a little better.
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