Bricked E2, re-flash MX25L12835F

[russellclarke]

Hi,

I bricked my E2 with corrupt firmware. It doesn't boot, just lights up a blank screen.

Can anyone provide a dump of the MX25L12835F flash memory?

[Weazley]

Would like to help but I dunno where I can extract it

[russellclarke]

You would need to open the case and read the flash memory. This can be done using an SOIC8 clip and a raspberry pi running flashrom. Similar to the process described here:

https://github.com/bibanon/Coreboot-Thi ... spberry-Pi


MX25L12835F is the small 8 pin IC near the centre of this photo, labelled IC8, just above the words 'Lead Free':

https://1.bp.blogspot.com/-_1rvXGoT1bA/ ... G_9292.JPG


I don't think I need it anymore. I dumped the memory and edited it to contain the stock firmware update. I broke the SOIC8 clip in the process so I can't test if it writes and boots until a new one arrives.

Comparing e2 and e2s flash memory could be useful for RE.

[russellclarke]

I don't think I need it anymore...

Scratch that, didn't work.

A flash dump from a functioning e2 would be very helpful. I don't know If I've corrupted the bootloader or damaged the hardware.

UPDATE:

I corrupted the bootloader while writing to the chip.

[bujbot]

I don't think I need it anymore...

Scratch that, didn't work.

A flash dump from a functioning e2 would be very helpful. I don't know If I've corrupted the bootloader or damaged the hardware.

Hey Russell,

I'm in the same boat with an e2 and am trying to get it past the blank screen. Have you had any luck recently? Were you able to obtain/verify the correct code for the MX25L12835F?

I noticed J9 and J10 appear to be for programming something, I had assumed one of them was the MX25L12835F. I have a bit of experience reading and flashing IC's and was thinking of just trying to read from both and see what happens.

Thanks!

[H45N]

Same here!

I used my Pi and Flashrom to extract the contents of the flashrom. It looks like the first portion of the memory is the actual bootloader.

Would really help if there is a dump file from a working E2 and E2S available.

[russellclarke]

Were you able to obtain/verify the correct code for the MX25L12835F?

Korg do not stock this, only a replacement motherboard for about the cost of a complete second hand unit. I asked here and on Reddit but no luck.

...was thinking of just trying to read from both and see what happens

I can read and write the flash chip using an ISP clip and Flashrom running on RPi. Somewhere between dismantling and rebuilding my e2 it became unresponsive...

[ZGaus]

Hey, I know the thread is a bit cold. I've cracked open my bricked Electribe2. (power button lights up screen but no text, no operation. power button won's shut it off, must be unplugged.) I'm hooked up to the IC8 with a SOIC clip to a Raspberry PI using the pinout from the Macronix data sheet. Flashrom will not find the chip. Before I desolder to try a direct connection, I figured I would ask if you found any tricks to read out the chip while it is still on the board.

I do have a running E2 that I can grab the file from, but I'd rather not desolder that chip to get it (and have 2 bricked E2s.)

Thoughts?

[ZGaus]

Update: I was able to read the working unit's chip with a CH341A dongle before the dongle died. So, I have a known good file, pm me and I can send it.

But in desoldering the bricked unit's chip to get it to register through the Raspberry PI's GPIO, I broke a leg off. And exact replacement chips are not available through the usual suppliers, so I have a couple equivalent spec chips coming, we'll see how it goes.

[russellclarke]

In the end I found I couldn't get a clean write using RPi and FlashROM, probably due to cheap connectors. I managed to fix it via JTAG using OpenOCD instead, see http://www.korgforums.com/forum/phpBB2/ ... p?t=124723.