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Netgear 490
#11
Read this:
http://www.spansion.com/Support/Datashee...56S_00.pdf

particularly:
Extended Address
The S25FL128S and S25FL256S devices support 32-bit addresses to enable higher density devices than
allowed by previous generation (legacy) SPI devices that supported only 24-bit addresses. A 24-bit byte
resolution address can access only 16 Mbytes (128 Mbits) of maximum density.
A 32-bit byte resolution
address allows direct addressing of up to a 4 Gbytes (32 Gbits) of address space.
Legacy commands continue to support 24-bit addresses for backward software compatibility. Extended 32-bit
addresses are enabled in three ways:

 Bank address register — a software (command) loadable internal register that supplies the high order bits
of address when legacy 24-bit addresses are in use.
 Extended address mode — a bank address register bit that changes all legacy commands to expect 32 bits
of address supplied from the host system.

 New commands — that perform both legacy and new functions, which expect 32-bit address.
The default condition at power-up and after reset, is the Bank address register loaded with zeros and the
extended address mode set for 24-bit addresses. This enables legacy software compatible access to the first
128 Mbits of a device.
The S25FL128S device supports the extended address features in the same way but in essence ignores bits
31 to 24 of any address because the main flash array only needs 24 bits of address. This enables simple
migration from the 128-Mb density to higher density devices without changing the address handling aspects
of software.


All they are doing is showing the flash chips banks as two separate flash chips so it is compatible with existing software. so when you reason that if finds 2 x 16mb flash chips, it will have 32mb total, its using a S25FL256 in compatibility mode. not a phantom image.
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#12
In my mind, it's 2 x 128. You are aware, despite your post, that folks get different reading's, for instance, The first anyone found out is it's a 256 chip, only to be told the above, making it 128, but if it shows as 256..? It must have 256 capabilities, even if it is only using 2 x 8mb banks.. so here we have a dual flash, which shows as 128mb, but also claim's to have a third., meaning there is more than 128mb space in order to move the files around..

Note this (quoting you) : The default condition at power-up and after reset, is the Bank address register loaded with zeros and the extended address mode set for 24-bit addresses. This enables legacy software compatible access to the first 128 Mbits of a device. Voila. MORE than 128. Since even here it declares access to the 1st 128mb, not the other..

Ps, I read usbjtag, re: this, wow, was in stitches..

1 - 0 to virgin.

And yes andy, I got 3 x 490's, working on one Wink

And if/when it's done, keep in mind gateway setting's wont work across modems, as in, you cant use gateway settings from one 490 and use it in another, I have tested this with 5 box's.. chances are the gateway setting's now check for private root cert, if it dont match what's in the gateway setting's, it wont work, however, most likely, each modem creates a different crc for the setting's, meaning one wont work in the other, for reasons I mentioned in other thread's, that like the bpi.bin not loading, wrong crc, unless it matches, it wont load.
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