10/28/2011, 05:59 AM
The HP Pre 3 is available in a number of different models:
1) EU Pre 3 (8GB) available in QWERTY, QWERTZ and AZERTY variations
2) Verizon Pre 3 (16GB)
3) AT&T Pre 3 (16GB)
The goal of this thread is to work out how to make an EU Pre 3 with 16GB of memory.
Note the daughter board inside the Pre 3 has nothing to do with the cellular modem, it holds the flash memory only and nothing else.
There is no way to change the cellular hardware of a Pre 3 as that circuitry is on the main board which is not removable or interchangeable.
The main board in the EU Pre 3 is marked "EU", the main board in the AT&T Pre 3 is marked "NA" and we assume the main board in the Verizon Pre 3 is marked "WP" (for World Phone).
The daughter board in the EU Pre 3 is marked "8G" and the daughter board in the AT&T Pre 3 is marked "16G". The goal is to swap those two boards, and then adjust the contents of the flash memory to make it work.
Note that the flash memory contains not only the normal webOS operating system partitions and user data partitions, but also contains the modem-related partitions and the tokens that define the configuration and factory calibration of a particular hardware device. So the contents of those flash memory partitions need to be swapped between the two devices as well (thereby putting them back in the device from which they came).
This thread will document the experiment, and if it is successful, how it's done.
Step 1 is to capture the flash contents for each of the two devices.
To do this, I have added a "qualcomm" target to the Meta-Doctor which captures all of the flash memory partitions to files.
Step 2 is to swap the two boards.
A simple matter of taking off the back cover, removing all the screws, removing the plastic inner casing, removing the daughter board screw and then gently prying the daughter board off from the main board. Reverse the process to reassemble.
Step 3 is to reprogram the relevant flash memory partitions with the device's original configuration.
It looks like partitions 7, 8, and 13 need to be swapped. Partitions 7 and 8 are the Modem ST1 and ST2 partitions, and partition 13 holds the tokens. The nduid and IMEI are stored somewhere in partition 7 or 8. The modem $HW VAR is read from the hardware.
Step 4 is to doctor both devices with the appropriate doctor, to reinitialise the other flash partitions to the correct contents.
The modem firmware is in the lower flash memory partitions, and the doctor for each device correctly flashed the modem firmware (EU Pre 3 modem firmware was upgraded from 3004 to 3500, AT&T Pre 3 modem firmware was downgraded from 3500 to 3004).
After doctoring, both devices seem to be working normally.
The AT&T Pre 3 now has 8GB of flash memory, and the EU Pre 3 now has 16GB of flash memory.
Step 5 is to test the cellular functionality, to ensure the modem configuration has been successfully swapped back into the original device.
Both devices are confirmed to have 3G data capability, on their original frequencies.