Electronics > Repair
TDS3052 stuck at splash screen
meduza:
Hello, and good day for everyone. My TDS3052 stuck at splash screen. Front panel LED's blinks shortly, floppy drives moves for a moment, and nothing happens then. I tried holding "B TRIG" during powering on, but it doesn't change anything.
Prehistory:
1. I bought TDS3052 (no suffix), it worked fine except date/time and settings aren't saved, and the floppy drive failed to read disks ("mass storage error").
2. I desoldered Dallas' DS1742W-120, and with surgery removed old battery and soldered a new one, installed the chip back with a socket.
3. I removed floppy drive, cleaned heads, and lubricated.
4. Assembled, and now I have the problem described above. I tried removing the Dallas chip, or just the battery, or the floppy drive, it doesn't help.
Does TDS3000 scopes boots if Dallas chip is not working or have wrong data in it? Maybe anybody can check that by removing the chip (if it's installed in socket), I will be thankful very much.
benj38:
Is the screen solidly stuck on the splash screen, or does it periodically flicker to momentarily show a blank white screen?
meduza:
It continuously shows the splash screen. I also checked the voltages +5, +15, -5, -15 on the TekProbe pins: they are ok.
benj38:
It is not very common, but I have seen my share of DS1742W chips where not only the battery is dead but the SRAM chip inside is dead as well. Depending on its mode of failure, I have also seen it prevent the scope from booting.
Given that you have performed surgery on the chip, and that the scope booted fine before the surgery, there is a good chance the chip died during the operation. I assume you verified that you installed the socket and the chip in the socket correctly.
Wrong data in the chip will almost never prevent it from booting, but who knows if some exotic combination of bits confuses the software enough?
If you have a programmer (like a TL866), it is not too hard to test if the chip is working or not by trying to program the time, and seeing if it accepts your programming, and that the time advances correctly. I have not seen a chip that passes this test that is bad.
You can figure how to do it by reading the datasheet. However, if you need help I can try tomorrow to provide some information to guide you.
You can also use the programmer to program the chip to a nice stable starting point that would guarantee success if there is nothing else wrong with the scope.
picburner:
The DS1742W runs at 3.3V (it doesn't have to be powered by 5VDC!) and many budget programmers don't even consider it.
In addition to being a sram it is also a timekeeper: the last bytes mapped in memory are reserved for the internal clock.
A unhappy combination of random data that ended up inside the sram during battery replacement could cause the scope not to start.
In this forum, somewhere, if I remember correctly there is the procedure to follow to restore the data contained in the sram, data of course to be customized with your serial number, MAC Address etc. etc.
Navigation
[0] Message Index
[#] Next page
Go to full version