Kindle 2 SD card

[mallen]

I had a few ideas here.

First,some of the serial ports can be reconfigured as SDI high speed serial busses,and you can do a four wire connection. All you need is to pick that up somewhere off the board and find a unused IO for a select,or perhaps re-purpose the power LED.

Second,the main storage on the kindle is an eMMC chip,which is just a memory card on a chip. I was thinking I could remove that completely,and wire a SD card slot in,and then just run everything off the SD card. Another option is,if I can tap in,I can find a unused IO line,or re-purpose the LED. The advantage of replacing the chip is,the drivers are there. It should just work.

Additionally,some,whether they be mini PCI-E or USB,have GPS,wifi and bluetooth.
Third,I realized that the cellular modem is actually running in USB mode. SO one of the three USB ports is routed to it. THere are a few options here. One is to get one of those flash drives that have an integral USB hub. Take the case off it,strip off the connectors,rework any capacitors or other components that are too tall with ones that are shorter,then cut the wires on the modem and wire it in between,with the wires coming FROM the connector going to the flash drive and the ones from the hub,going to the modem. Now the modem runs through the hub,and the flash drive is on the USB buss.

Another variation on that is the idea of making a daughter board to go between the modem and the connector that would tap in there,or removing the connector entirely,and replacing it with some sort ribbon cable connector where I could tap in.There are lots of ideas but they all take up more space. Then I thought maybe I could get a half length modem card. One that I could rewrite the IMEI on to match the modem Im swapping out,and put my SIM in it. They shouldn't know the difference. And then it hit me,can I get a modem that HAS an SD card slot on it,and sure enough,I can. So thats my thought. I'm on the lookout for one,but it has to be one that I can rewrite the IMEI on. Of course,it can be done on most any,but some there is info on doing and some there is not.

My other thought is,where does the third USB port go. One is the external one. One is to the modem. But is the third in use,and is it routed anywhere. I have a board from dead kindle 2 here and Im going to take the chips off it this weekend and trace the wire from the pads.

If Im really lucky those lines are connected to some of the test points on the back of the board,and I can run them where I need with conductive ink. That would be perfect as I would prefer to avoid replacing the modem due to the expense of having to buy one.

I just thought of another option. See if I can find a USB GSM dongle that when removed from its housing is small enough to fit,and wire it in. Some have a card reader function on them.

[brianinmaine]

Ready, Set, Go! I'd love to see some pictures! Sounds like a LOT of work for very little payback? Good luck!

[hawhill]

If the K2 board is anywhere near the KDX, K3 and later boards, it is a multilayer board and it will be a more than tough job to trace the wires... I'm not sure if there is PCI-E. I don't think so.

The documentation of the SoC used is open, but it is - again - a tough job to re-route IO channels. As the K2 is not sold anymore and I guess there are less and less functional units in the wild, this is probably mainly to the benefit (and fun!) of the OP. So - have fun! Sounds like a nice project.

[knc1]

Originally Posted by hawhill

If the K2 board is anywhere near the KDX, K3 and later boards, it is a multilayer board and it will be a more than tough job to trace the wires... I'm not sure if there is PCI-E. I don't think so.

The K3 model does have the modem on a PCI-e card.
Check the teardown videos indexed in our "Master Index" for the other models.

Originally Posted by hawhill

The documentation of the SoC used is open, but it is - again - a tough job to re-route IO channels. As the K2 is not sold anymore and I guess there are less and less functional units in the wild, this is probably mainly to the benefit (and fun!) of the OP. So - have fun! Sounds like a nice project.

**PLUS**
The functions of the I-O pins go through a (programable) cross-bar switch.
I.E: A pin is not always dedicated (hardwired) to a specific function until the device comes up and runs the vendor's (Amazon's) code.

If you remove the parts from the board, it will be hard to tell what functions are being switched to which traces.

Note: With a very bright light you can "see" into the board to follow the buried traces, either side of any ground plane or power plane that limits the view.

Using a bright light, a decent digital camera, and an image processing program (like: Gimp) can make the buried traces "visible".
For example, see my photos of the traces to the K3 serial port connector.