Quote:
Originally Posted by WaseemAlkurdi
1. It depends on the Kindle model concerned.
I have a Kindle Touch (two of them, one dead) and a Kindle 7th generation (KT2).
The Kindle Touch wouldn't accept 3.3 volts (and I tried), requiring Geekmaster's level-shifter circuit, or at least a resistor (and I don't have one, so I left them without serial port access). It didn't burn out or anything when I connected the 3.3v adapter, but didn't send any output either.
But the 7th gen Kindle happily accepted the 3.3v adapter without an issue. Check around here to see if your Kindle Paperwhite model is 3.3v-tolerant. I'd guess that it is indeed. But is it really difficult to wire a resistor? You don't even have to solder it, you just wrap the cables around its pins.
2. That's like my setup. In the picture below from my 7th generation Kindle, I took another jumper cable from an old ATX case (had to settle for two-pin, more on that later) and soldered it to the Kindle to create a permanent serial port, then glued it to the sides so it won't move around when the Kindle is closed.
Then, when I need serial access, I would connect Tx and Rx to these two, and ground is from a third, bare-ended jumper cable wrapped around a Kindle motherboard screw.
3. No, not that fast. You first need to read the serial output to find out what's the issue. If it's eMMC failure, then what good would copying a new image be? But on the other hand, and since you never updated that Kindle before, it might just be a borked OTA update, done behind your back and interrupted for some reason.
You need the image for your Kindle model. But since you're on the serial port, it isn't really a mortal sin to copy the wrong image.
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Couldn't find a straight answer for the 3.3 - 1.8 question just as you said some said it worked some said it didn't as a general rule it's recommended to stick with original design and even the "level shifter circuit" uses resistors for this reason.
I honestly don't mind soldering it in the problem is i don't have any parts and have to order and wait a few weeks for them :/
Following this nice guide i found:
http://ebookrepairs.com/kindle-tips/...t-to-a-kindle/
seems like the LM1117 1.8V mentioned there should do the trick.
I guess he has the resistor connected to the jumper but where should i connect mine if i don't have one? if i solder to the ping would need to solder the other end to the kindle? or maybe i should just make a Y shaped jumper head?
Looking for my kindle board i stumbled upon this image and now i'm not sure about the connections, TX,RX,GND but what is the 4th?
I'm taking about the red wire in this img:
https://www.mobileread.com/forums/attachment.php?attachmentid=145410&d=1452450964[/IMG]
Regarding your setup i'm wondering why you didn't just make a hole in the case for the jumpers thus avoiding opening the kindle every time? Also curios you used a female to male jumper wire to bridge the soldered cables and the serial board?
Lastly i should have said so but my kindle was never hooked to an AP so it never had any connection and was only used offline so no OTA was possible, no idea how it got messed up on it's but obviously not ruling out HW failure so you're right about taking it slow.
Just to be clear tho, you are saying that while using serial it's impossible to ruing the device with a bad\improper image?