RE: [avrdude-dev] avrdude and FT2232

[Wouter van Gulik]

> I have a bunch of programmable chips which need to be programmed in
> production. There are a couple of AVR's (mega8) and then a bunch of
> other processors (ARM) and logic (Xilinx, Altera, Lattice) which need to
> be programmed. AVR's use SPI, others JTAG.
> 
> As the SPI interface and the JTAG use the same number and type of lines,
> they can be handled with a single programmer, as far as the pin numbers
> are correct.
> 
> I have been able to accomplish this with a custom-made parallel port
> programmer and slight tweaking of avrdude (plus some other open source
> programming software). However, parallel port is no more, and I need to
> move into USB.
> 
> The problem here is that direct bit-banging on USB is very slow. On the
> other hand, numerous USB dongles (such as Olimex USB-JTAG, Amontec)
> utilize the same chip, FT2232. This chip has the MPSSE engine which
> talks both SPI and JTAG rather fast when configured correctly.
> 
> Now my intention is to implement this functionality into avrdude (=
> support for FTDI2232-based MPSSE). However, before doing anything, I
> would like to know I am doing the right thing.
> 
> - where should I start? I have the source of avrdude 5.5, and I have a
> general idea of what happens in it. Should I get the newest source from
> the CVS, or is it better to stick to the released one?
> 
> - libftdi and d2xx seem to require slightly different handling. Is it
> necessary/desirable to make both? (I am slightly inclined towards D2XX,
> but I do understand the open source point very well.)
> 

My guess is that libftdi is the best thing. It relies on libusb which is
already present. Libftdi could may be distributed along with avrdude. 
I do not know about d2xx's requirements or licenses etc

> - has someone done something to this direction already?
> 

Yes some have, take a look at: http://savannah.nongnu.org/patch/?4330
This may be a bit out dated (back to 2005)

> - anything elsi I should be aware of?
> 

Just make sure it runs on Windows and *nix otherwise the chance of
acceptance are probably very low...

Good luck,

Wouter