Siglent 1202X-E recovery - Page 1
Forum section: electronics / repair

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 12:30:37 am
content: Hi there guys. I picked up a Sds1202x-e as a repair project off of EBay. The listing said it had a booting problem. I did manage to get it to boot eventually by a hard reset and a long 30min wait. When it did boot it displays something like noise on the screen. Full length of the graticule no matter what scale. It has the latest firmware and nobody has been inside of it. I was thinking maybe a firmware flash gone wrong? I've been trying to flash othe firmwares with no luck. Mostly because getting it to reboot is nearly impossible. You can spend hours trying to get it to boot into the main screen again. It looks new. Came in the original box with all accessories and manual. Nobody has even changed the little probe rings.

author: tautech
author_rank: Super Contributor
timestamp: March 16, 2020, 01:16:52 am
content: Hmm, interesting.Have you tried to do the Self Cal ?Wonder why the previous owner didn't try for a warranty claim ?

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 02:07:41 am
content: I have done a self cal and it took a little of it out but not much. It takes anywhere from 1hr to never to complete. Usually it just hangs. I have managed to downgrade the firmware and if anything it made it worse. I'm leaning towards a hardware issue now. I may have to crack it open. I agree it's very strange that someone didn't try for a warranty claim. it only had 22 boots when I got it. I am now up to 144 and I have only been playing with it for a day.

author: tautech
author_rank: Super Contributor
timestamp: March 16, 2020, 02:58:17 am
content: OK thanks. I'll go fishing for some answers/solutions for you.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 10:11:18 am
content: well this doesn't look normal. Upon further inspection it looks like the glue they used to fix the heatsink to the processor. Someone got messy at the factory. It's a thick, very hard substance. Crappy.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 10:20:44 am
content: All around the heatsink. Not sure if it's the problem though. It makes sense that it would be the reason that it hangs and won't boot half of the time.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 10:46:28 am
content: Not conducive though.Moving on. Going to have a look at voltages and ripple on the outputs of the PSU.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 11:54:11 am
content: All voltages on the main board appear to be correct and all clock signals are present.That's about all I can do. Well maybe I'll hook up a serial connection and see what that is saying....gurrrrr

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 12:54:54 pm
content: That could be a good idea. Of course provided Siglent chose to output some kind of helpful diagnostic messages. There's a Linux system working under the hood. If you get a console, please post the boot log, I'd like to have a look.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 01:01:29 pm
content: Here is a text file with the output..this is where it fails to boot. FPGA problem? I'll try to get one where the boot is sucessful also. I wasn't sure if I should attach it as a file or just paste it in here.itedit:Actually finally finished booting with no further output. So this is it.

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 01:04:34 pm
content: Quote from: jonathanlemoine on March 16, 2020, 01:01:29 pmI'd attach it as a file. Easier to handle than inline text.

author: Mark19960
author_rank: Regular Contributor
timestamp: March 16, 2020, 01:13:05 pm
content: It's not happy about one of the FPGAs in the instrument and that doesn't bode well.Code:insmod: can't read '/usr/bin/siglent/drivers/udc-xilinx.ko': No such file or diyCan't load the driver to even talk to the FPGA?There are other things in there like a CRC error and it not being able to copy from USB.

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 01:15:58 pm
content: Quote from: jonathanlemoine on March 16, 2020, 01:01:29 pmThe log lines seem to have been cut at 80 columns. But there's nothing jumping out, actually. Can you configure your terminal program to capture the full lines and add a timestamp in front of each line?

author: goaty
author_rank: Regular Contributor
timestamp: March 16, 2020, 01:24:26 pm
content: So the TOis a similar unlucky person like me who also tries to buy broken stuff for repair but doesn´t have Shariar´s luck (signalpath) for finding graeat equipment with minor errors

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 01:28:00 pm
content: Quote from: Mark19960 on March 16, 2020, 01:13:05 pmThe CRC error is normal if the u-boot environment has no backing store in the NAND (because it isn't provided or it has never been initialized).Not being able to load the linux kernel from USB is also not an error. That looks like part of the development setup still part of the firmware. It successfully loads the kernel from NAND afterwards.The FPGA related messages are a bit suspicious, but they could be just normal debug output. Maybe if you look around on the forum a bit you'll find a boot log from a working device. I know Dave Jones has put boot logs from Siglent scopes up for download, maybe check out the thread regarding the test and teardown of this scope.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 01:40:52 pm
content: i copied and pasted from the terminal. On my screen the colums weren't cut off. maybe something happened when i copy it to LibreOffice. Mayabe I should make the file with the command line instead?Maybe next time. I don't do this often guys sorry. Here is an odt file instead of text incase something was lost in the txt format.This time where it goes into a kernal panic. As you can see it fails 785s into the boot process. It does take a long time to boot when it does.

author: Mark19960
author_rank: Regular Contributor
timestamp: March 16, 2020, 02:37:20 pm
content: ODT looks better to me.There is a kernel panic related to the FPGA.Might be worth some checking about to make sure all of the power supplies for the FPGAs are up and running.

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 02:45:01 pm
content: The kernel panic certainly isn't a good sign. It looks like the software is waiting for a certain status from the FPGA which doesn't arrive.Code:[ 785.178931]  *pgd=00000000This means the CPU tried to access memory that isn't mapped, could be the equivalent of a null-pointer de-reference.The stacktrace is also a bit weird, it failed in sched_show_task(), called from rcu_print_detail_task_stall_rnp(), this is a standard diagnostic kernel function that belongs to the RCU subsystem (read-copy-update). It appears the kernel detected a stuck task and tried to call it out and then panic'd while it tried to print the task data.It sounds like there's something very wrong, at least something that the software was never prepared to handle sensibly.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 03:01:36 pm
content: This is interesting. Figured I'd try to see why it won't complete a recalibration.

author: Mark19960
author_rank: Regular Contributor
timestamp: March 16, 2020, 03:14:00 pm
content: I know there are chaps a lot better at this than I certainly but some module that may not have loaded and then a bunch of errors about a read-only filesystem.Seems to start pointing in my mind to the flash being corrupted or bad.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 04:01:57 pm
content: Maybe someone will have an idea. Until then I have a paperweight. I thought about reflowing the FPGA but I don't know if that would do anything and may just make things worse.

author: tautech
author_rank: Super Contributor
timestamp: March 16, 2020, 06:40:15 pm
content: Didn't think you'd be so keen to rip it apart and go sniffing just yet.I haven't heard back from Siglent but now they have lots of additional info to digest.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 08:11:47 pm
content: I should be leaving it alone but I figure I might as well learn some things on something that doesn't matter if I break it... Don't get me wrong I'd love to get it working. I bought it for $285 CAD + shipping so it would be an expensive paperweight. Right now I'm just sniffing around to see if I can see anything odd... The trouble is I don't know enough. For instance why is the root filesystem mounted read-only. How can anything be configured if nothing can be changed? Seems odd. But I know nothing. I appreciate everyone's help though. I really need it. I'm aware it may be beyond my ability to fix in the end but I like to try. It's all a learning experience.

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 08:29:29 pm
content: Quote from: jonathanlemoine on March 16, 2020, 03:01:36 pmI see you're using minicom. Ctrl-a w switches on line-wrap mode, ctrl-a l allows logging into a text file. Ctrl-a n toggles different timstamp modes.Quote from: jonathanlemoine on March 16, 2020, 08:11:47 pmI didn't see rootfs mounted read-only in your first log, but if it is, that's a sign of a corrupted NAND flash.Quote from: jonathanlemoine on March 16, 2020, 04:01:57 pmThat's probably the last thing I'd try. Carefully applied pressure might have the same effect temporarily and be less dangerous.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 16, 2020, 09:47:53 pm
content: Ok so I tried applying some pressure too the chips while booting and it had no effect.Any file I open with vi is read-only. Also I can't create any files as it returns an error that the filesystem is read-only.I guess we found the problem then? Corrupted NAND? I take it there is no fix like a re-flash? Ah well. It was a nice journey.

author: thinkfat
author_rank: Unknown
timestamp: March 16, 2020, 10:53:10 pm
content: Ubifs doesn't have a recovery tool, but you can try reading each file to force the kernel to check them. Then try remounting the file system read-write.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 17, 2020, 12:46:03 am
content: Thanks. I'll give that a try. If it doesn't work I I'll have to wait for a parts scope or sell it for parts... Or just use it for experimentation.

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2020, 10:07:32 am
content: Quote from: jonathanlemoine on March 17, 2020, 12:46:03 amHold your horses....from factory tech support:From the fault, we adjuge that it is most possible the hardware fault. Need to replace the mainboard. This customer come from Canada. So please ask him to contact SIGLENT American office or info@siglent.com

author: goaty
author_rank: Regular Contributor
timestamp: March 17, 2020, 11:00:54 am
content: Is it behaving always the same during startup ?You could try ice-spray on memory, flash or Xilinx chip.Also measure supply rails with scope if there is some dips.Maby re-soldering/re-flowing (or replacing) ram/flash could also help if they are not BGA.

author: Mark19960
author_rank: Regular Contributor
timestamp: March 17, 2020, 11:16:17 am
content: Well, if Siglent repairs it for a reasonable price it's certainly worth it to have them do it.

author: thinkfat
author_rank: Unknown
timestamp: March 17, 2020, 11:42:25 am
content: Mainboard exchange ain't gonna be cheap, though.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 17, 2020, 02:11:16 pm
content: Quote from: tautech on March 17, 2020, 10:07:32 amThank you. I will contact them. I figured as much. But I'm thinking it will be expensive as thinkfat says. I'm not in need of a board right away because I have a SDS2102 (hacked of course). If it's resonable (let's say $200) then sure, it's a no brainer.Quote from: goaty on March 17, 2020, 11:00:54 amI have ordered some ice-spray yesterday to try just that. I have tried heat, also pressure and it behaved the same...with that said it's not the same everytime. Most times it doesn't boot at all. Usually the only way to get it to boot is to press the math button durring startup as per the manual. Sometimes that works and sometimes it doesn't. 90% of boots are very slow (10-15min) always saying the fpga address error 0x21 and sometimes also 0x19. Also evey successful boot leaves you with a read-only filesystem preventing a self-cal. And always having the "noise", for lack of better word, on the trace. ( makes it impossible to trigger off anything useful.)Quote from: thinkfat on March 16, 2020, 10:53:10 pmGave it a try but the scope hung part way through the file reading so I'm not sure if it's going to work. I am going to give it another try though.

author: thinkfat
author_rank: Unknown
timestamp: March 17, 2020, 05:50:30 pm
content: You mentioned checking all power rails, but maybe you could have a look at particularly the power rails that support the main processor? It's a Zynq-7000 series Xilinx chip, two Cortex-A9 plus a veritably sized Virtex-class FPGA. If the power supply is glitching, all bets are off. Checking for glitches on the power rail for the NAND flash might be a good idea as well.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 17, 2020, 06:31:12 pm
content: I'll have a look. Thanks

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2020, 06:43:18 pm
content: Quote from: jonathanlemoine on March 17, 2020, 02:11:16 pmUntil you contact them who knows but I would hope it's under warranty.The SN# codes give the date of manufacture and the last 4 digits are just the unit # of that particular production run. Care to share all but the last 4 ?

author: jonathanlemoine
author_rank: Contributor
timestamp: March 17, 2020, 07:00:53 pm
content: Serial: SDS1ECDX3R****

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2020, 08:11:55 pm
content: Quote from: jonathanlemoine on March 17, 2020, 07:00:53 pmQ3 2019 production I think.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 17, 2020, 08:52:25 pm
content: I contacted Siglent with my problem. They responded and said that they would do a warranty if the serial number is withing the 3 year period. So I just sent then my serial and am currently waiting for a response.

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2020, 09:13:14 pm
content: Quote from: jonathanlemoine on March 17, 2020, 08:52:25 pmSo have I.QuoteOhio should sort this all out for you but AFAIK it's AHrs there now so you might not get a reply until the 'morrow.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 17, 2020, 09:26:52 pm
content: Thanks! Yeah I figured it would be too late today. I have nothing but time for a little while anyway. I have lots of other projects that I would like to start. I don't think I'll check any anything else until I hear back. Just incase I do something very bad. Lol it would be my luck. It's a little disappointing though. It's so much more gratifying fixing something yourself.

author: tautech
author_rank: Super Contributor
timestamp: March 17, 2020, 09:34:54 pm
content: Quote from: jonathanlemoine on March 17, 2020, 09:26:52 pmYeah but how deep do we go with trying to fix it if it's still within warranty ?I lost a customers one a few months back but a different fault to yours and the warranty claim was no issue.You'll like this little 1202X-E over your older 1202X.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 18, 2020, 12:24:18 am
content: Oh it will be good to get it fixed under warranty for sure. Actually I only bought it with the hope of flipping it. I wanted to play with it but I wasn't sure I wanted to keep it. I have a 2102 not the 1202x...I bought it off eBay as an open box item and it said it was a 2102x. I was disappointed when I opened the box and found it was not an x model.. But it was new. Seller was a dick and didn't take responsibility for it but for the price it was still good so I kept it. I also have a 500mhz HP but it's not as cool as the new ones. I don't do this for a living. I'm a heavy equipment operator, electronics is just a hobby. Learn a little bit with everything I fix.

author: tautech
author_rank: Super Contributor
timestamp: March 18, 2020, 12:37:32 am
content: Quote from: jonathanlemoine on March 18, 2020, 12:24:18 amOh, OK. Did you see what Defpom did with the SDS2102 I sold him ?

author: jonathanlemoine
author_rank: Contributor
timestamp: March 18, 2020, 09:04:16 am
content: Yup. And thanks to the wonderful people here I got all the codes to unlock the features. Funny thing is TheDefpom is kinda the reason I got into electronics. I started way back aligning/repairing CB radios. It's been growing from there and I watch most of his videos.(he's sort of an idol). Among many others. I didn't realize you were the one that sold him that. That's cool. Small world.

author: tautech
author_rank: Super Contributor
timestamp: March 18, 2020, 09:50:11 am
content: Dropped the SDS2104X Plus to him yesterday and he did a 38 min video on it last night !

author: jonathanlemoine
author_rank: Contributor
timestamp: March 18, 2020, 02:40:09 pm
content: I watched it first thing this morning. That is one nice scope. I could never justify it but a guy can dream.

author: goaty
author_rank: Regular Contributor
timestamp: March 18, 2020, 03:08:25 pm
content: Just wished these chinese manufacturers would get a grip on their model numbering scheme.SDS1000DL+, SDS1000CML+, SDS1000CFLSDS1000X-E, SDS1000X, SDS1000X+SDS2000X-E, SDS2000X, SDS2000X Plus,SDS5000XGimme a break

author: tautech
author_rank: Super Contributor
timestamp: March 19, 2020, 12:54:37 am
content: Quote from: goaty on March 18, 2020, 03:08:25 pmYou missed a heap more that are only made for Asian and rebrand markets.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 19, 2020, 01:04:27 am
content: I haven't heard back from siglent. I think they forgot about me. Or maybe the are not in the office anymore with the Corona virus. I'll send them another email tomorrow I guess. They were quick with the first response but now they left me hanging.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 19, 2020, 02:13:15 pm
content: Well they got back to me. It would be under warranty but they won't because I opened it. No suprise there. I guess I didn't need to spend all of that time protecting the warranty sticker.lol. So a repair with the shipping would run about $200 USD. Alternatively they could also get me a discount from a vendor on a new one. If I got it fixed I could probably recoup some of my money or I could throw it in the parts bin.... Can't really decide. Any opinions?

author: thinkfat
author_rank: Unknown
timestamp: March 19, 2020, 03:10:32 pm
content: $200 seems more than reasonable for a mainboard exchange. You'll have a practically new scope for $400, right?Parts bin - what parts exactly do you plan to salvage? I my experience, specialized electronics never get reused unless you're in a repair business. You can strip the power supply, the knobs, some rotary encoders maybe, but the really valuable stuff (main CPU, FPGAs) are useless because you'll not be able to transplant them. What else could there be - maybe some buck converter chips, some coils, the ADC, RAM and NAND (all BGA I bet), the frontend amplifiers - nothing close to the money you already paid for it. The screen - maybe, if you can figure out how to make use of it.

author: jonathanlemoine
author_rank: Contributor
timestamp: March 19, 2020, 04:36:10 pm
content: Well that's true I could spend the money and sell it. Then I'd get most of my money back.In the next few years there might be some scope on eBay that somebody dropped and broke the case and screen. I thought I might go that route.On a side note I decided to go to town on it since I had nothing to lose. I reflowed the FPGA and now it's completely dead lol. No boot. I kinda figured that would happen anyway. It's all good.