On Friday, 24. September 2010 11:04:44 Uwe Bonnes wrote:
> >>>>> "Thomas" == Thomas Jarosch <thomas.jarosch@xxxxxxxxxxxxx> writes:
> Thomas> Hello Uwe, looking at this code:
>
> Thomas> int ftdi_eeprom_build(struct ftdi_context *ftdi) { ... if
> Thomas> ((eeprom->chip == 0x56) || (eeprom->chip == 0x66))
> eeprom-> size = 0x100;
> Thomas> else
> eeprom-> size = 0x80;
>
> Thomas> ... ... size_check = 0x80;
>
>
> Thomas> Shouldn't we init "size_check" with eeprom->size?
>
> No!
>
> The strings may only take up 0x80 bytes. This is how I interprete AN_121
> "accessing the EEPROM User Area". And with the data layout in a 56/66
> chip, string data would then end above 0xff.
Hmm, if I read AN_121 correctly, the complete storage area
for all strings is only 96 bytes / 0x60 - for all chip types/eeprom sizes.
Could you check with MProg if they limit all strings to a total of 96 bytes?
If yes, we can greatly simplify our "size_check" code like this:
if (manfacturer_size*2 + product_size*2 + serial_size*2) > 96)
explode_and_die();
AN_121 also mentions the "manufacturer ID" string additionally
to the "manufacturer" string. Any idea what that is?
Thomas
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