Pimp Your Zaurus: 1gbyte Nand Flash Upgrade, ...first seen on my Zaurus C750 ;) Options

[ranma]

Hi all!

I recently looked into how the NAND is hooked up on the Zaurus (my C750):

CODE

          TP6
            TP5
          TP4
---------   TP3
|Xilinx | TP2
|CPLD   |   TP1
|       |
---------

TP1 => CE0
TP2 => CE1! (unused?)
TP3 => /WP
TP4 => /WE
TP5 => ALE
TP6 => CLE

I also found two nicely compatible 8GBit TSOP48 Toshiba Flash Chips in a CNMemory 2GByte CF Card.

So I soldered one of the 8GBit chips on top of the already existing 512MBit chip (all signals except CE are shared).
Soldering was a bitch though (pins did almost, but not quite reach the pins below), but with lots of solder, cursing, solderwick and patience
I eventually had all relevant pins connected.
Since the Linux kernel unfortunately always enables/disables both CE signals I couldn't simply use the CE1 signal from the CPLD, but for now
(first tests) I hooked up CE to the Cathode of the Green EMail-LED (which is normally always off and the transistor acts as an inverter, so
'on' == low, exactly what I need) and a 10k pull-up.

The system boots fine and a hacked up 'fiddle with CEs and read IDs' kernel module finds both Chips just fine:

CODE

Trying to read id from Flash on CE0
Got maker=98 device=76
Trying to read id from Flash on CE1|GreenLED
Got maker=98 device=d3

According to drivers/mtd/nand/nand_ids.c maker 0x98 is 'Toshiba', device 0x76 is a 'NAND 64MiB 3,3V 8-bit' and
device 0xd3 is the shiny new 'NAND 1GiB 3,3V 8-bit' (Yay!).

This should actually already exercise all control signals, so the only remaining task is to modify the built-in sharp_sl nand driver to properly support two chips.

[the_oak]

I thought long ago someone was stating that 128MB RAM was possible with the Z.

I think it was Speculatrix who (unsuccessfully) tried that. Brave soul. It would have been a success but the chip cracked, or something like that.

[speculatrix]

I thought long ago someone was stating that 128MB RAM was possible with the Z.

I think it was Speculatrix who (unsuccessfully) tried that. Brave soul. It would have been a success but the chip cracked, or something like that.

no, I was trying to fit a bluetooth module inside my sl-6000, turned out I had the wrong type of module - there are many variants of Mitsumi devices. in the process of reassembling it I was squeezing the USB wifi module on and snapped a RAM chip. I tried to find someone who could do BGA "surgery" to remove the bust ram chip and fit a new one, and possibly populate the empty slots for more memory too.

that zaurus is still b0rked - the person capable of BGA surgery was unavailable and the RAM chips are very hard/impossible to find.