[LinuxBIOS] Fun easy question. 512Kb or 256Kb

[Peter Stuge]

On Mon, Feb 06, 2006 at 10:41:02PM -0800, Adam Talbot wrote:
> Fun easy question. 
> Messing about with my new board, and have an easy question.  So I have 
> both the SST 39SF020 and the 39SF040 flash chip. My payload is just 
> filo; so I can fit Linuxbios on the 256Kb or the 512Kb flash chip. Is 
> there any reason to use the 512Kb?
> Faster, slower, any thing else like that?

It depends on the second line of numbers on the package.

SST 39SF0x0(A) is on the first line
45-4C-NH(E) or something similar is on the second line

45/70 is read access speed in ns
4 is minimum life in write cycles
C is temperature range (Commercial 0c->70c or Industrial -40c->85c)
N is PLCC
H is 32 leads
E is lead-free

Page 20 of http://www.sst.com/downloads/datasheet/S71147.pdf


But, I doubt you would even be able to measure difference in speed
between 45 and 70 ns versions. :)


//Peter