August 9th, 2019, 20:00
August 9th, 2019, 22:55
framp wrote:Just an update for everybody facing a similar issue: I managed to login into the looper via UART. The looper is runnign QNX, a posix compliant Unix. I was able to dump the NAND data and a tool called etfsctl.
August 9th, 2019, 23:22
August 9th, 2019, 23:24
October 5th, 2019, 7:06
October 6th, 2019, 17:39
framp wrote:As I said I spent a lot of time understanding the etfs format and design. The code I created to recover all files which had transactions in the raw etfs dump is available here in github. It's not very elegant code because I had a lot of trial and error coding loops but finally it recovers the files. Maybe it's useful for somebody in the future who has to recover data from an etfs filesystem.
October 10th, 2019, 13:57
fzabkar wrote:How did you dump the NAND?
etfsctl -d /dev/etfs2 -R /mnt/sdfs/etfs2.img
Did you dd the NAND "drive" to an SD card?
Did you copy (cat) individual files to your SD card?
You say you scanned your dump for RIFF headers. Do the unplayable WAVs correspond to deleted loop data that were discovered by the scan?
October 10th, 2019, 14:07
HaQue wrote:1) the format could be different than straight .wav
2) post processing done by decoder to not use all of the .wav spec or in a different manner than intended
3) your dump included information such as SA bytes or ECC or something that further needs to be stripped out
4) files are not stored in a totally concurrent fashion... I have seen recently while hacking some games consoles that ROM files for example have a block of DATA and if the ROM is bigger than this, the next block is stored somewhere else, not straight after.
5) your dump might be ok, but not ECC corrected, so bit errors are present. (Linux systems that use NAND should have this built in though at a driver level)
6) may be some binary to ascii conversion happening, but I would think files would be totally screwed up if this were the case (thinking like specifying BINARY option in some rudimentary older protocals)
kudos or getting this far. I remember when I first got a prompt from a Microvax 3400 after a friend came across 2 complete but disassembled systems. right at the start of accessable internet, searching was in infancy, and I had help from a Tafe college lecturer that correctly identified the plug that looked like a LAN port as a terminal adapter port. not knowing anything about unix, terminals etc. this opened up a whole new world
October 11th, 2019, 3:35
June 3rd, 2020, 20:53
June 5th, 2020, 13:22
June 15th, 2020, 3:21
May 29th, 2022, 16:44
framp wrote:Well, this wasn't my Jamman Stereo. I would have created a backup on a memory card on a regular base. But my son who asked me for help didn't do this - unfortunately So the only source for data recovery was the NAND which unfortunately was cleaned up at some point in time
June 4th, 2022, 15:07
March 24th, 2024, 20:44
Powered by phpBB © phpBB Group.