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stysis · 07-15-2014, 08:53 AM

When I read Nephiel's post describing how he copied waveforms to new screens I was determined to give it a go.

I've done it in much the same way but with some different techniques which I thought I'd share here.

The biggest difference was that I used a Raspberry Pi rather than an Arduino. There is a very clear guide to flashing chips with a Raspberry Pi here.

The other key difference was my method for connecting to the chip on the Kindle screen. Nephiel must have more dextrous fingers and better eyesight than me, I couldn't get the sewing pins to sit where I wanted them.

So I had to come up with something less fiddly. I had some long headers lying around and after a bit of bending of legs and some scraps of wood to make a jig, I had a more secure set up.

The 150R resistors described in the Raspberry Pi guide were not needed (I didn't have any 150R so tried 220R and got no result, so I took them out). There is also no need to make the connection to pins 3 and 7 of the chip. Connecting the flash chip is also described in the Flashrom web site here.

When you connect a new screen don't assume the rom chip is blank. Make sure you read the chip as a first step before erasing or writing. I've looked at 2 new screens bought on ebay, one had a perfectly good waveform file which I now have a copy of.

Happy flashing!

One of the headers used to connect to the chip.

The mocked up jig with screws clamping the chip and headers in place. (The extra 2 headers are just there to make the wooden clamp sit flat.)

Close up of the headers in contact with the chip. Pin 1 is at the bottom left. Note that pins 3 and 7 are not connected.

The whole set up.

07-15-2014, 08:53 AM	#57
stysis Junior Member Posts: 3 Karma: 38820 Join Date: Apr 2014 Location: Australia Device: Kindle Keyboard	When I read Nephiel's post describing how he copied waveforms to new screens I was determined to give it a go. I've done it in much the same way but with some different techniques which I thought I'd share here. The biggest difference was that I used a Raspberry Pi rather than an Arduino. There is a very clear guide to flashing chips with a Raspberry Pi here. The other key difference was my method for connecting to the chip on the Kindle screen. Nephiel must have more dextrous fingers and better eyesight than me, I couldn't get the sewing pins to sit where I wanted them. So I had to come up with something less fiddly. I had some long headers lying around and after a bit of bending of legs and some scraps of wood to make a jig, I had a more secure set up. The 150R resistors described in the Raspberry Pi guide were not needed (I didn't have any 150R so tried 220R and got no result, so I took them out). There is also no need to make the connection to pins 3 and 7 of the chip. Connecting the flash chip is also described in the Flashrom web site here. When you connect a new screen don't assume the rom chip is blank. Make sure you read the chip as a first step before erasing or writing. I've looked at 2 new screens bought on ebay, one had a perfectly good waveform file which I now have a copy of. Happy flashing! One of the headers used to connect to the chip. The mocked up jig with screws clamping the chip and headers in place. (The extra 2 headers are just there to make the wooden clamp sit flat.) Close up of the headers in contact with the chip. Pin 1 is at the bottom left. Note that pins 3 and 7 are not connected. The whole set up.