RAM update on DXG

[praneeth.aithara]

Dear Friends,

I own a kindle 3 which I bought 2 years ago. It was damaged recently and it's out of warranty period. Yesterday, I bought a used Kindle DXG from a friend, which was only 6 months old and it's brand new.

Now, I read on this forum about installing 3.1 firmware on Kindle DXG and there were few users who reported that Kindle DXG RAM is only 128 MB while Kindle 3 RAM is 256 MB.

Please help me to understand, if this is possible: To replace 128 MB RAM of Kindle DXG with 256 RAM of Kindle 3 and then upgrade it to 3.1 firmware. How should one do it and Will that have any adverse effect on battery.

Thank you so much.

[geekmaster]

At the very least, you need SMT rework skills and tools, and you may need to route an additional address line. That sort of thing has been a lot more popular for upgrading wireless routers and other embedded linux devices, but I have not seen any reports of people trying to upgrade RAM in a Kindle yet. Be sure to publish your results.

EDIT: Because the upgrade to 256MB uses a power of 2 for the row and column address in the RAM chip(s), you probably do NOT need to add any additional address line in this case. You may also need to modify the u-boot bootloader (and perhaps other code) to initialize and use the extra RAM.

[knc1]

Originally Posted by praneeth.aithara

Dear Friends,

I own a kindle 3 which I bought 2 years ago. It was damaged recently and it's out of warranty period. Yesterday, I bought a used Kindle DXG from a friend, which was only 6 months old and it's brand new.

Now, I read on this forum about installing 3.1 firmware on Kindle DXG and there were few users who reported that Kindle DXG RAM is only 128 MB while Kindle 3 RAM is 256 MB.

Please help me to understand, if this is possible: To replace 128 MB RAM of Kindle DXG with 256 RAM of Kindle 3 and then upgrade it to 3.1 firmware. How should one do it and Will that have any adverse effect on battery.

Thank you so much.

With the proper tools, any of the parts on the Kindle is replaceable.
You will need the special tools used to re-work SMT (Surface Mount Technology) assemblies.

To replace a specific part with an alternate part (rather than with an identical part, as in repairing the device), you need the technical reference material on the devices in question.

A more specific answer:
In the case of the DDR RAM chip -
Many manufacturers of these devices produce them in "families", all members of the family share the same physical pin-out (in this case, ball-out) with the same signal connection plan.

Look up the RAM part number in your DX, find if it is a member of a "family" of devices and if that "family" contains a part with higher storage capacity in the same package.

Now compare the electrical characteristics of both parts - -
Then you can answer the question about effects on the battery.

If you have the special tools, or access to the special tools - -
If you find a physically and electrically alternate part for the existing part - -
Then you need to find out if the alternate part is one of those which the SoC chip in your DX can initialize.
Refer to the SoC chip technical documentation to answer that question.

If you find that the SoC can initialize the alternate part - -
Then check the U-Boot and Kernel sources to see if they can also properly control the new device type.
Both sets of sources will have a list of the devices they can control.
You may have to customize those lists.

Let us know how you get on with this project.

[knc1]

Originally Posted by geekmaster

EDIT: Because the upgrade to 256MB uses a power of 2 for the row and column address in the RAM chip(s), you probably do NOT need to add any additional address line in this case. You may also need to modify the u-boot bootloader (and perhaps other code) to initialize and use the extra RAM.

The U-Boot code for the DX-2.5.8 firmware that I recently read has both 128Mbyte and 256Mbyte initialization available in the source code.

But if I recall correctly, it is a build-time configuration option - -
If my memory is correct, it would have to be rebuilt.

On the bright side - it is easy (on this DX firmware) to get u-boot written into the write-protect portion of flash where it normally lives.
Its "erase flash" function un-locks, erases flash, then copies the executing copy of u-boot back into the u-boot partition(s), and then re-locks the flash write-protection.

- - - At least that is how I read it, I did not actual test it on a device to see if my understanding was correct. - - -

[geekmaster]

Originally Posted by geekmaster

...
EDIT: Because the upgrade to 256MB uses a power of 2 for the row and column address in the RAM chip(s), you probably do NOT need to add any additional address line in this case. You may also need to modify the u-boot bootloader (and perhaps other code) to initialize and use the extra RAM.

Let me clarify that. What I meant to say is that because 256MB is a square layout (same number of rows and columns), you should not need to route an additional address line.

However, if you were upgrading from 64MB to 256MB, you may well need to add such an additional address line (to be used for the extra row and extra column address bit). Such memory quadrupling is not all that uncommon for severely memory-limit devices such as wireless routers. But for a kindle, no worries!

[twobob]

Originally Posted by geekmaster

Let me clarify that. What I meant to say is that because 256MB is a square layout (same number of rows and columns), you should not need to route an additional address line.

However, if you were upgrading from 64MB to 256MB, you may well need to add such an additional address line (to be used for the extra row and extra column address bit). Such memory quadrupling is not all that uncommon for severely memory-limit devices such as wireless routers. But for a kindle, no worries!

Reminds me of the work on the http://therdf.net/ RDF's minecraft server. : )

http://therdf.net/2012/floating-point-adder/

or


amazing what you can do with enough switches and lines