Expand flashROM from 16Kb-->64Kb

[KILLorBE]

As the title says I want to expand my flashROM from 16Kb to 64Kb, I hear you ppl screaming that's impossible....well it's not that simple, the ROM is actually 64Kb but everything above 16Kb is written as 0xFF (so I was told), in order to flash the ROM with a 64Kb file I need to 'unlock' the remaining 48Kb.

Anyone, Anybody, Someone, Somebody got a clue?

Don't ask me why I want to do that, when it works I'll let you know, and if you already know....SEND ME THE FILE!!!

 

[PsYcO CyBrArIaN]

I believe that the ROM file size is adjustable through command prompt or a program.
I was just searching Google.com and it has been tough to find anything not related to portables or Commadore64's and Ataris...

 

[bluce ree]

ok here's your problem,

it may not be possible.

the reason is this:

you may not have enough address lines to access all of the flash on your flash chip.

address lines work like this:

address0--has 8bits of data
address1--has 8bits of data
address2--has 8bits of data
.
.
.

16kb = 2^14 16384 bytes of data are addressed by 14 data lines.
64kb = 2^16 65536 bytes of data are addressed by 16 data lines.

if you don't have 16 data lines, you can never access any flash memory above the 16384bytes.

what i would do first is this: look at the flash chip, then look at the chip that interfaces with it. then look on google.com, by typing in their part numbers. if both the flash chip and your interface chip say they have 16 datalines, you're probably home free, if not, you're screwed.

you can probably use 128kb, 256kb or whatever the hell size rom you want, but if the chip that's supposed to be reading it doesn't have atleast 16 address lines, or some unique multiplexed way of grabbing data, you can't actually read anything above 16384.


Can you give me your EXACT PART NUMBERS, of the flash chip and the chips that's closest to it? I may be able to help you.