Is this something that could be upgraded on an existing LM? Or is there more than just soldering involved?
It's an interesting idea, though you'd need very good soldering skills to do it, the flash memory chip is tiny. An SMD re-work station would likely be needed.
While even if you had the skills to do it and did do it whether or not it'd work is the question, and Kevin touched on that, I don't believe it'd be quite as an insurmountable task as it looks though.
Without knowing exactly what is stored in the flash memory and what isn't this is just a best educational guess for the "hard parts".
- The unique ID is likely stored in the PIC, not the flash memory. There is memory sections in the PIC for just that type of purpose. Another candidate is the unique ID is programmed as part of the transmitter in the LM but I think that's much less likely the case.
- The program that controls the device (an LM in this case) there are two possibilities: 1: The program is written to the PIC in it's entirety or 2: Some or all of the program is written to the flash memory and pulled in into the PIC as needed. I have no idea which of these it is. If it's all in the PIC then changing out the flash memory wouldn't require pre-flashing the flash memory with the product program.
- Could, as they stand now, the -2 access more than 4 Megabytes and the -3 access more than 8 Megabytes of memory? Possibly not without a change to the product program so that they could use the extra memory available.
So definitely not insurmountable but I'd say probably beyond the realm of 99.9% of people here. Changing out the flash memory is the easy part (with the right tools of course, not an everyday soldering iron), figuring out the rest is the hard part.
- Tim