I don't know if anyone has dealt with something similar and gathered the relevant knowledge, but I would like to share this with you.

My yesterday's problem:
One of my two 2GB cd-cards for the SP-808 was full. No big deal, there is this „clean-up disk“ function, which brings back some space, as you know. So i cleaned up in standard-mode and could go on happy sampling. So far so good. But after a rebooting of my SP-808, it could no longer read the cf-card. There was this „No Sp-808 disk“-Message on the screen asking if the disk should be reformated. What. The. Fuck. This cf-card was really, really important to me, because I used it to record a lot of brilliant samples during my recurring chill and vinyl seesions for a few years, acually since i've got the sp-808 a few years ago. And there this was one unreleased song with vocals by my xgirlfriend on it. Shocking, I needed a really big drink.
I inserted the card into an USB card reader on my trusty winxp laptop and started Roland's SP-808 Wav Converter. But the program didn't recognize the card either.

Then I copied everything from the corrupt cf-card to the hard disk of the pc and headed to the kitchen to get me a very large Drink.


The SP-808 data structure:
When i came back, i looked into the „corrupt cf-card“- folder with windows explorer and found this (root folder):
SONGLIST.VS2 - a file
SONG0000.VS2 - a folder
Inside SONG0000.VS2 there are these files:
EFFECT__.VS2
EFFECT1__.VS2
SAMPLE__.VS2
SAMPLE__.BAK
PADBANK_.VS2
and then:
TAKE0000.VS2
TAKE0001.VS2
TAKE0002.VS2
TAKE0003.VS2
...
TAKE0362VS2
and then:
VSNG0001.VS2
VSNG0002.VS2
VSNG0003.VS2
...
VSNG0011.VS2
last but not least:
VSNLIST.VS2
WAVELIST.VS2

This is basically the structure, how the sp-808 saved data in files/folder. The logic seems to be obvious. All its samples are stored in the "TAKE"-Files. Information about samples and sample parameters are saved in SAMPLE__.VS2 and Wavelist.VS2 and SAMPLE__.BAK. Or maybe SAMPLE__.BAK is there to provide the undo-function of the 808.The names of banks and the assignment of samples are stored in PADBANK_.VS2. Songs are stored in the VSNG-Files and in the VSNLIST.VS2. User Effects are stored in EFFECT__.VS2 and EFFECT1__.VS2.

So, what could i do? First of all, I reformatted the cf-card with the SP-808. Then I recorded a sample on pad 1 and saved. I took the card out, put it back into the usb-cf-card-reader and restarted Roland's Wav Converter. It found the disk immediately and I could listen to my sample on pad 1 in the program. The data structure on the cf-card was similar to the data structure described above, but there was only one take-file, namely "TAKE0000.VS2, and no songs, i.e. no VSNG-files.
Without exiting Roland's Wav Converter, I swapped the Take-file on the cf-card with the one with the same name from my "corrupt-cf-card" folder. And Tadaaa! The sample from my corrupt card was played by the program and I could even save it as a wav file.


Rebuilding the CF-Card:
This was a heavy try-and-error-procedure.
First of all i copied over all Take-Files into the SONG0000.VS2-folder of the fresh formated card and put it back in the 808. Same message. Then i swapped the SAMPLE-files, too. Did not work either.
Then i thought of kind a masterfile containing lists or indexes, the relational data, path information, where everything is stored etc., maybe SONGLIST.VS2. And when there are more Take-Files existent in the folder, then bang, error. But exchanging this file did'nt bring any solution.
so i think there was either case a: this master file is the corrupted file on the card or case b: information about the sample/take-files in this master file was missing.
So, because my corrupted card has been full of samples (over 300 TAKE-Files), i downloaded the 250MB Demo Disk from Roland which is in the same data structure with over 400 TAKE-Files on it.
I swapped the TAKE-Files with my "corrupted ones", loaded the card into my SP-808 and boot. There was a "please wait" message for about 3 seconds after the boot, right when the main windows appears. But first successfull step! Between all the untouched demo-samples i found my samples here and there in the different pad banks, which got their demo names.
A few of my samples played like they should, but most sounded awful and distorted, with wrong pitch and wrong timestretch. So i headed back to the pc with the cf-card and changed the SAMPLE__.VS2, the SAMPLE__.BAK and the WAVELIST.VS2 with the ones from the "corrupted cf-card"-folder.
Next try on SP-808: Yes! All my samples were now sounding perfectly, like they should! Only the demo samples sounded fucked up now.
Next try-outs: Swapping the PADBANK_.VS2 brought back my padbank names and the original sample assignment. Hell yeah!
Swapping all the VSNG-Files and the VSNLIST.VS2 and all my songs were back again. Playable and editable without any flaws!
Important, i think: Between every step i did a full safe on the sp-808. The first save maybe already updated and repaired the corrupted main information file (SONGLIST.VS2?). I don't really know.
But the card works, i also could restart the sp-808 again without any problem.

Next step was to take a freshly formatted card and rebuild this content.
I took every file from the corrupt-cf-card-folder from pc, EXCEPT the SONGLIST.VS2 ( and except the EFFECT__.VS2, EFFECT1__.VS2, but i don't think that's elemental. More important: i took these files from the card i created before and had got running (and saving) on the sp-808 again.

This Worked!

(Actually i used same physical card - all i did was happy file swapping in winxp).

So i will do some further investigation to validate if the clean SONGLIST.VS2 from Rolands Demo Disk was the key here or the possibility to do a full save on the sp-808 again and overwrite the corrupted file(s) and having a clean main information file this way.
Both lead to the same technically i think, but would be good to know.


Can anybody confirm this? Or got further information here?

Good chances exchanging EFFECT__.VS2 and EFFECT1__.VS2 will restore user efx patches. And yes, it would be awesome if someday we could read and edit Rolands proprietary VS2-format. Even though, there aren't that many SP-808 headz with working zipdisk-readers or cf-card-readers nowadays. But i don't know...for this evening i'm just happy to have my samples and songs back. Salute!