Getting lots of CRC errors on my PSX images


GOGO

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I had stored a bunch of PSX CD images on my 32GB SD card. It's the left slot from where I'm booting the OS too. After about six month I felt the need to fire up some of my PSX games using PCSX ReARMed r19, as I did in the past.

But stangely I got glitches with gfx and sound I never had before. PCSX ReARMed even crashed. I deleted the appdata of PCSX ReARMed r19 to eliminate potentially wrong settings, downloaded the PND again - but no luck.

The time I created the game disc images I also created a .md5 file for every image. So next step I copied the images over to the other sd card in the right slot and was informed about read errors by Thunar File Manager two or three times. I tried Midnightcommander - I got read errors at the same files and points at the progress bar. But most files where copied without any error message.

Then I put the right SD card with the game disc images in my windows netbook and was checking the integrity of every image and volia: nearly every image has a CRC mismatch, not just the images where I saw the read error message but nearly all images that were copied just fine.

I did a quick search via google (board) and the wiki but no luck. So the two questions are:

1. Are there known issues with files getting corrupted over time if stored on the same card as booting the OS from for some reason? Or maybe other known issues regarding big files getting corrupted on Pandora?

2. Is there a tool that allows me to create and verify md5 check sums on pandora comfortably? At the moment I have to check the md5 using a windows application (named QickSFV). It's computing the check sum of every selected file and create a file with all the file names and check sums. If you want to verify, click on the .md5 file to have the application opening and checking all the files. I did look at the repo but again without luck.

Any advice is appreciated. Thank you.

PS: I have a 1Ghz with SZ 1.55, kernel 3.2 installed on sd card

edit: worst typos eliminated
 
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Pandora has the "md5sum" command-line program. You can pipe the output to a text file, and use this text file as input to check data files later. The files from your other program may or may not be compatible.

http://linux.die.net/man/1/md5sum
 
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What brand is the card? I've a 32gb SanDisk class 4 card with loads of my Playstation images on it, never had any problems (over several years) - but did find things going bad on a 'Bytestor' card once.
 
@HelenF Beeing a windows user, I knew I will have to learn this linux command line thing sometime. I think I have to learn it know.

Any suggestions where to begin? Maybe a beginner's guide that's also applicable for the pandora?

@Asmo When I try to unmount the right sd card (same model as the left one) I get the error message "unable to unmount volume P3_Trance was probably mounted manually by the command line." ... errr .. no! I don't even know how to use it properly. I have to turn my pandora off in order to remove the right sd card.

anyway, it' a transcend 32gb class 10 card -- most probably this one: http://www.amazon.de/Transcend-Extreme-Speed-Class-Speicherkarte-Lesen/dp/B003P3MCXW/ref=sr_1_9?ie=UTF8&qid=1410623928&sr=8-9&keywords=transcend+32+gb+sdhc
 
@HelenF Beeing a windows user, I knew I will have to learn this linux command line thing sometime. I think I have to learn it know.

Any suggestions where to begin? Maybe a beginner's guide that's also applicable for the pandora?
Linux consoles tend be much more similar to each other than the graphical user interfaces of different devices. You can pretty much use anything you find on the web, you only notice the difference when you use it a bit more, and by that time you'll be able to cope with the differences. :)
I did a quick search for some introduction which looks decent to me, I found this one: http://www.linuxcommand.org/lc3_learning_the_shell.php

And the most important two things: if you add "-h" or "--help" to a command you'll almost always get a help (often longer when you use --help than with -h), if you use "man command" you'll get a manual page for command. Also helpful: "help". Just enter it, you'll see.

Don't do dry learning, open that web page and terminal on the Pandora and try around. As long as you avoid "rm" (deleting files) there isn't a lot which can go wrong.
 
Strange things happen. Earlier when I got the error messages while coping the game disc images, the thunar file manger crashed. At that point I was unable to open the main menu (pandora symbol on task bar) and a few desperate clicks and button presses later the task bar was gone and the system freezed. battery reset was needed - remove and insert back the battery.

Now when I browse the web using firefox I encountered something similar. I wasn't able to open the task bar menu by pandora-key. I had to use the touchscreen. But when I tried to open an app, only some activity on the left sd card was indicated by the drive LED. But the apps doesn't open up.

I had to restart my pandora once again. I assume all my files including system files getting corrupted resulting in strange behavior of my pandora. Damn it.

I guess I have to make a backup as soon as possible, grab another sd card and setting up a new system, right?  ARGH|

I did a quick search for some introduction which looks decent to me, I found this one: http://www.linuxcommand.org/lc3_learning_the_shell.php
 

Learning the shell sounds great. I'll do just that. Thank you.
 
Okay, so some things:

1. When the OS crashes, you can always hard reset without removing the battery (more convenient): Pandora button+Power button (it's not actually a button, how is it called? Slider?)

2. Maybe you should do a full reflash to be sure your system works properly. Not sure, but those issues sound like maybe when the system crashed the firmware was corrupted too. You should be able to look up instructions on the Wiki, it's easy.

3. You should always have backups.

4. Run "fsck /media/nameofyoursd" (nameofyoursd is where your SD is mounted, look around in Thunar {or terminal :) }, you'll see) in terminal. This will check the file system of the SD for errors, telling you if there are any and fixing them automatically if possible.

If you had a second SD card to test that would be good, but I think for now doing 2, 3 and 4 should be enough, then wait what happens.

Maybe someone knows of a tool to check whether SD cards are working properly? I'm sure there was something like this.
 
Maybe someone knows of a tool to check whether SD cards are working properly? I'm sure there was something like this.
Check the file system first as you said.
H2testw is widely recommended on Windows. Maybe F3 would work on the Pandora: http://oss.digirati.com.br/f3/

Or just fill it up completely with largeish (non-repeating) files and see if they read back the same. If possible, it would be good to try it in a different device to see whether the problem is the card or the Pandora.
 
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Yes. It was f3 I was thinking about. Even typed "f3" into a search engine tentatively, but should have added some other keyword I guess, too much stuff called f3...

I know I've used that on the Pandora, just not sure whether there is a build available somewhere or if I just compiled it for myself... can't do that right now.
 
Maybe add a verified(using a program like RapidCRC) Redump PS1 bin/cue image to your fully formatted SD card from your PC. Play it on the Pandora, including multiple saves, for a while over a day or two. Then recheck the CRC32 again on your PC to see if it changed any. If different, it's probably the card if it's one of the cheap brands, as those love to corrupt. Patriot and Sandisk never gave me problems if it turns out to be so.

Sorry you're going through this.  :(
 
Maybe add a verified(using a program like RapidCRC) Redump PS1 bin/cue image to your fully formatted SD card from your PC. Play it on the Pandora, including multiple saves, for a while over a day or two. Then recheck the CRC32 again on your PC to see if it changed any. If different, it's probably the card if it's one of the cheap brands, as those love to corrupt. Patriot and Sandisk never gave me problems if it turns out to be so.

Sorry you're going through this.  :(
f3 would be much faster, easier and more reliable if it is available. Can someone make a pnd?
 
I found this article in the german wiki: http://wiki.openpandora.de/Neuinstallation_der_Firmware (reinstalling the firmware).


Just to get things straight. Fireware means this pandora-optimized angström linux, the operating system of the pandora?


If I flash it the normal way, the so called NAND (internal flash memory of pandora) will be replaced. So I have to obtain the SZ 1.56 zip-file that is intended to be installed on a sd-card in order to be able to boot from sd card afterwards?


I like to boot from sd catd because it does not wear out the NAND, right? First thing I did over a year ago after receiving my pandora was installing SZ 1.55 to sd card. There is a pnd in the repo, that is formatting the sd card and copying the system files to sd card. Does this still apply for SZ 1.56? http://repo.openpandora.org/?page=detail&app=sd-install-2011-03-10


Somewhere I read that I have to pay attention that the kernel version matches the OS version. At the moment, my boot screen tells me I'm booting to kernel 3.2, SZ 1.55. If I install SZ 1.56 to a spare sd card, do I have to watch for the kernel version in any way?


@Saber thanks for your compassion. Very kind.
 
If your Windows computer can use SD cards without going through the Pandora, the simplest thing to try would be to check the file system of the suspect card on Windows (right click on the drive in My Computer, open the properties, and look for the error checking option), and then run h2testw on the card (you need to download that).

EDIT: I missed the part where you installed the OS on the same card. The above will only work if it has a file system that Windows understands. But if not, it might be worth reformatting it and running h2testw.

Even if it does have a Windows-compatible file system, h2testw won't check the areas which have files on them already (but may cause damage to the existing files if there is something wrong with the card). So probably best to empty the card and start again anyway.
 
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Maybe add a verified(using a program like RapidCRC) Redump PS1 bin/cue image to your fully formatted SD card from your PC. Play it on the Pandora, including multiple saves, for a while over a day or two. Then recheck the CRC32 again on your PC to see if it changed any. If different, it's probably the card if it's one of the cheap brands, as those love to corrupt. Patriot and Sandisk never gave me problems if it turns out to be so.


Sorry you're going through this.  :(
f3 would be much faster, easier and more reliable if it is available. Can someone make a pnd?
As suggested, I'd like GOGO to have the card fully formatted to fat32 and the game image checked through the Redump.org on a different machine(the Windows PC) with RapidCRC first. It's good to have an outsider's opinion so to speak. Not saying the Pandora is being temperamental with the SD card, but it's best to know where the corruption begins before the emulator is loaded.  
 
I found this article in the german wiki: http://wiki.openpandora.de/Neuinstallation_der_Firmware (reinstalling the firmware).

Just to get things straight. Fireware means this pandora-optimized angström linux, the operating system of the pandora?

If I flash it the normal way, the so called NAND (internal flash memory of pandora) will be replaced. So I have to obtain the SZ 1.56 zip-file that is intended to be installed on a sd-card in order to be able to boot from sd card afterwards?

I like to boot from sd catd because it does not wear out the NAND, right? First thing I did over a year ago after receiving my pandora was installing SZ 1.55 to sd card. There is a pnd in the repo, that is formatting the sd card and copying the system files to sd card. Does this still apply for SZ 1.56? http://repo.openpandora.org/?page=detail&app=sd-install-2011-03-10

Somewhere I read that I have to pay attention that the kernel version matches the OS version. At the moment, my boot screen tells me I'm booting to kernel 3.2, SZ 1.55. If I install SZ 1.56 to a spare sd card, do I have to watch for the kernel version in any way?

@Saber thanks for your compassion. Very kind.
Ah, you are booting from SD. Then you don't need to reflash the NAND, but do that SD install again with the newest firmware. The kernel should be included with the firmware and match it, I don't think you need to worry about that.
But in that case to test the SD (first thing to do) you should either boot from NAND or do it in another PC as Saber suggested. I don't necessarily agree with him, but my argument is hypothetical anyway as we don't seem to have an f3 binary for the Pandora anyway.

Just write a large amount of data to the card in any way you want, then read it back and check the checksums.
 
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I like to boot from sd catd because it does not wear out the NAND, right?
You don't have to do it, pandora uses ubifs that does wear leveling (makes sure to not write to the same block repeatedly), so that allows it to survive very large number of writes. Also PND system is designed not to write to NAND, only to SD card. There have been no reports of weared down NAND from anyone over the years, you'd make your life easier by running the OS from NAND, as it's designed to be used.
 
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Will bad blocks be marked as bad by the system if it tries to write to them multiple times and fails?
 
Thank you all for your help. :)

I found this wiki post: http://pandorawiki.org/%C3%85ngstr%C3%B6m I will do exactly as described under " Full fresh installation; To SD card (external)"

Actually this is the second time I'm replying because as I tried to add a screenshot, everything was gone. An hour worth of finding the right words and typing them. :wacko:

Anyway, as soon as I arrive back home I will install Super Zaxxon - actually it is SZ 1.61, not SZ 1.56 as I wrote earlier - on another sd card. I ordered one together with my pandora, guess the brand is Polaroid.

One last question though. HelenF was kind enough to tell me roughly how I can create md5-hashes for my game disc image files, pipe those hashes into a file and verify the integrity of the game disc image files later by computing the md5-hash again and compare the check sums with what is store in the file with the hashes.

the linux shells seems a bit like the windows (or DOS for that matter) command prompt ("C:\>"). I'm used to the DOS thing but I have no clue about the file / folder structure of Linux nor the structure of the Linux commands and parameters. I'm willing to learn all that stuff but as I really have to find out what is going wrong with my pandora, I need to know how to create a md5-hashes-file now and how to verity them afterwards.

So looking at the game disc image files and folder structure in the screenshot below, what would you type into the shell after opening the terminal to obtain a file containing the md5-hashes of the Disruptor.ccd, Disruptor.img and Disruptor.sub?

140914-152012.png

And second, what would you type into the shell to verify the files by comparing the current md5 hash with the one previously stored to the file?
 
I found this wiki post: http://pandorawiki.o...ki.org/Ångström I will do exactly as described under " Full fresh installation; To SD card (external)"

Actually that is a bit of a confusion point on the wiki.. That section describes how to install a fresh install to the NAND FROM the SD card, not install SZ to THE SD card. It's worded poorly. 


I've been meaning to have it changed, but I can't seem to get into the wiki. 
 
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Code:
t4b@sabine ~ $ mkdir example
t4b@sabine ~ $ cd example/
t4b@sabine ~/example $ ls
t4b@sabine ~/example $ touch test test2 test3
t4b@sabine ~/example $ ls
test  test2  test3 
t4b@sabine ~/example $ md5sum test* > test.md5
t4b@sabine ~/example $ ls
test  test2  test3  test.md5
t4b@sabine ~/example $ md5sum -c test.md5 
test: OK
test2: OK
test3: OK
t4b@sabine ~/example $
Code:
cd ~/PSX-Roms/Disruptor
md5sum Disruptor *.ccd *.img *.sub > Disruptor.md5
md5sum -c Disruptor.md5
First line changes directory, next puts the checksums of all .ccd, .img and .sub files in the current folder in file Disruptor.md5, last checks whether the md5sums in Disruptor.md5 are correct.
 
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