Third Party > Repairing and Upgrading Rockbox Capable Players

ams sansa e200 memory upgrade

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mx:
As far i know, the e200v2 uses an 64MBit chip, 8MB, 16b wide. My idea is to replace it with another bigger compatible chip, but i have two questions.
The installed memory is 1Mx16b, 4 banks. I read about the arm memory controller and it supports up to 512Mb in 32Mx16, 4 banks configuration. After patching the bootloader i think this could work, BUT the 64MBit chip uses 0:11 addres lines, and for more i need additional addres lines. Are they wired or not, so replacing the chip will provide no improvement?

Second, im not sure how the flash storage is connected. First i thought NAND-NAND controller of AS3525 SoC, but later i found the flash appears as an SD card sotrage. So is this correct? NAND-NAND SD controller inside the Sandisk SoC - SD controller of the SoC?

I would like to populate the empty place in my 2GB player with an 4GB chip from an SD card or USB drive.

1. is the maximum 2x4GB chips? Or can i use 2x8GB chips and the controller copes with it?
2. need i use SanDisk chips or any other could work too?
3. If i replace both NAND chips, my idea is to load the firmware via JTAG to RAM, and run a formware upgrade.

And the last question, extracted and disassembled anyone the first stage bootloader from the SoC ROM?

I read the forums, but found no correct answers to this upgrading ideas.

Thanks.

saratoga:

--- Quote from: mx on March 28, 2012, 09:19:41 AM ---As far i know, the e200v2 uses an 64MBit chip, 8MB, 16b wide. My idea is to replace it with another bigger compatible chip, but i have two questions.
The installed memory is 1Mx16b, 4 banks. I read about the arm memory controller and it supports up to 512Mb in 32Mx16, 4 banks configuration. After patching the bootloader i think this could work, BUT the 64MBit chip uses 0:11 addres lines, and for more i need additional addres lines. Are they wired or not, so replacing the chip will provide no improvement?
--- End quote ---

The memory is internal to the AS3525 chip, not a discrete IC.  Most likely, none of the address lines are externally connected since there is no external memory.


--- Quote from: mx on March 28, 2012, 09:19:41 AM ---Second, im not sure how the flash storage is connected. First i thought NAND-NAND controller of AS3525 SoC, but later i found the flash appears as an SD card sotrage. So is this correct? NAND-NAND SD controller inside the Sandisk SoC - SD controller of the SoC?
--- End quote ---

IIRC, theres an SD controller IC on the player which sits between the NAND and the AS3525 chip.


--- Quote from: mx on March 28, 2012, 09:19:41 AM ---1. is the maximum 2x4GB chips? Or can i use 2x8GB chips and the controller copes with it?

--- End quote ---

You'd probably have to ask Sandisk.  I don't think anyone knows how their SD bridge chip works.


--- Quote from: mx on March 28, 2012, 09:19:41 AM ---And the last question, extracted and disassembled anyone the first stage bootloader from the SoC ROM?

--- End quote ---

I think funman looked at it, but I'm not sure in how much detail.

mx:
The AMS chip has some onchip RAM, but there is also an external SDRAM chip connected, in my case Samsung K4S641632K-UC75.

I try to solder some NAND IC, hope it will work. maybe the sd controller can detect them.

saratoga:

--- Quote from: mx on March 28, 2012, 03:20:54 PM ---The AMS chip has some onchip RAM, but there is also an external SDRAM chip connected, in my case Samsung K4S641632K-UC75.

--- End quote ---

Sorry, was thinking of the Clip series.  I forgot that the e200v2 and fuzev1 had external memory.   

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