Re: [avrdude-dev] avrrftdi driver port selection

[Hannes Weisbach]

Am 15.01.2014 um 16:55 schrieb Jonathan Schneider <address@hidden>:

> On 15 Jan 2014, at 13:29, Hannes Weisbach <address@hidden> wrote:
> 
>> Am 15.01.2014 um 10:52 schrieb Jonathan Schneider <address@hidden>:
>>> 
>>> But I am absolutely baffled as to what port to specify.
>> The FT2232D should work out of the box, if you didn’t change the
>> VID/PID.
>>> 
>>> If I put usb:999 or even complete garbage after the -P I don’t get any kind 
>>> of meaningful error but does seem to know whether I have the FT2232D 
>>> plugged in regardless of -P. It looks as if port selection is somehow 
>>> completely automatic and -P is ignored. What if I have more than one 
>>> FT2232D ?
>> You need to put the USB VID/PID of your FTDI in hex after -P like so:
>> '-P 0403:6010‘.  Why did you feel the need to put '-P usb:n‘ in the
>> avrdude command line?
> 
> Thank you Hannes. May I suggest the manual be updated ?
Of course. Please supply a patch ;)
> 
> Useful to know since my FT2232D board has an EEPROM that is nominally setup 
> like the JTAG section of a Marvell Sheevaplug with different IDs (if it has 
> been programmed properly which it might not have been).
You can also have a custom avrdude.conf in which you can declare a
custom programmer which 'inherits‘ from avrfrtdi but has a different
VID/PID.  Then you can use that programmer with -c and save the typing
of -P <…>.  If you think other people might benefit from such a new
programmer declaration you can supply a patch for that too.
> 
> There is still the question of how do deal with having more than one FT2232D 
> present. It’s not a problem for me right now but could be and should be 
> catered for.
It is.  You can set a serial number in the EEPROM, which avrftdi can
use to select a matching chip.  There should be an option for avrdude
to supply a some sort of "usb serial number“ - but I don’t know which
option it is or whether it is implemented.

Best regards,
Hannes