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Subject: Re: [EEPROM branch] Amount of data in ftdi_read_eeprom

From: Thomas Jarosch <thomas.jarosch@xxxxxxxxxxxxx>
To: libftdi@xxxxxxxxxxxxxxxxxxxxxxx
Date: Fri, 24 Sep 2010 21:12:16 +0200
On 09/24/2010 04:42 PM, Uwe Bonnes wrote:
>     Thomas> This used to be "eeprom->size/2". Any reason you changed that?
>     Thomas> There's also (old) code to guess the eeprom size.  Maybe we
>     Thomas> shouldn't do that anyway.
> Because I think is is easier that way. We have a fixed buffer, read all 0x200
> bytes in a single libusb calls and if 0x80.. 0xff is a mirror of 0x00..0x7f,
> we have a 93x46 ...

Think of an TYPE_R chip. We can't predict how future revisions
of the same chip react to reading out-of-bounds eeprom addresses
as it only contains a 128 byte eeprom. Same applies to future
FTx232 chips with an attached 93x46 eeprom.

What about reading the first 128 bytes, check if the
eeprom is configured to be an 93x55 or 93x66 and
then read the second half of it (if needed)?


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