[Gnuk-users] Making use of FST-01 SPI flash in Gnuk token

[NIIBE Yutaka]

Duncan <dguthrie at posteo.net> wrote:
> As I understand it, the devices sold via Seeed Studio Bazaar had the
> link to the documentation on this flash.
>
> This strikes me as a useful thing. I'd like to accomplish the following:
>
> 1. Build the latest Gnuk token firmware
> 2. Install my public key and miscellaneous other data onto the SPI flash.
> 3. Expand the size of the flash (I am thinking this might not be
> possible, from glancing over certain datasheets).
>
> In the original firmware, how did the flash appear? I assume it had a
> filesystem on it, probably vFAT? If so, can we make use of a different
> filesystem, just out of interest?

No, the flash is not used at all by the firmware (Gnuk).  We only have a
little access code for that in gnuk/tool/stlinkv2.py.  That's all.

>From hardware point of view (wa have space on PCB), I put the serial
flash to FST-01, hoping it will be useful.  But, I was not able to find
any useful way, in fact.

In FST-01G (I manufactured last year), I drooped the serial flash (as
the part is not available any more).

Expanding the firmware, it would be somehow possible to give the access
to the serial flash through USB Mass Storage Class to users, but it will
be slow, given the condition of available memory size of STM32F103.

If we do by USB Mass Storage Class, file system handling is done by host
PC.
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