Repair attempt TC-Electronic Nova System: DSP Audio (guitar)

[krivx]

I have tried reseating the large flat cable with power on, this seems to reset the entire system as if I have cycled the power cable.

I have also run the self-test (delay and boost held down while powering up) and I could go all the way through, no issue with any buttons, LEDs or encoders. The unit still freezes when powered up.

The ATMega would be nice fix, surely it is programmed though? I can attempt to desolder and dump it but I imagine it's code protected.

Would a dump of the main socketed ROM chip help you out with your unit? Mine has a v1.2 sticker.

[krivx]

I just went through this thread with the help of Google translate - funny to see the same names come up again and again in the DIY guitar electronics communities, Dirk_Hendrik seems to be everywhere

http://www.gitaarnet.nl/forum/showthread.php?167760-Nova-System-Repair&s=307ac744598859f01a90bc0cd256cb47

[krivx]

I tried to immediately run the factory reset routine on power up. It ran, reset and now everything appears to work. I'm thinking there may have been corrupt preset data stored that was causing a lock up on footswitch presses. I have heard of this only working temporarily, so I will probably keep the screws out for the next few days. If a factory reset fixes it again I might look at swapping whatever memory holds preset data. If any measurement from a working unit would be helpful then let me know.

[obiwanjacobi]

Yeah, sure - if its not too much trouble.
Just post it here as an attachment.
Thanx! 

[krivx]

Just getting to this. I dumped it with a Tl866 and PLCC32 adapter but I'm not totally certain it's a good copy. Looking at the hex I don't see many recognizable strings, usually I see a copyright notice somewhere.

GNU strings does find text like this:

  >DIMD IpmueR iecdev< 
  >    - sySmet -    < 
  >P -ser teB /kna - < 

Which looks like mangled text for the menus, so text may be stored in some unusual way (?)

[obiwanjacobi]

Looks good, I could find preset names in the first block. (2 blocks: FF-data1-FF-data2-FF)

The menu strings are in the ATmega, I think - you will not find them in the DSP ROM.

Thanx.

[krivx]

You are right, each letter of the preset title has some extra characters in between.

This might explain some of the freezing issues reported online, saving to flash may cause corrupted data which locks up the unit when it's reloaded. My unit recovered by a full factory reset. I have seen accounts of swapping the flash chips between units to revive them too.

[fenderender]

"A bit off topic maybe but I am planning to get a Nova system and modify it for 4-cable method. From your pictures i can make a qualified guess that the drive unit is on a separate board. Is that so? and could you take some pictures of that maybe since you have already disassembled it?"

Hello guys. I would really like to know if this mod. could be done else I'll have to spend some bucks to see myself   

[obiwanjacobi]

FYI: I have an almost complete reverse-engineered schematic of the front panel board. Shoot me message if you're interested.

[obiwanjacobi]

Was all my work for nothing!? 

https://service-tcgroup.tcelectronic.com/nova_system.asp