Re: [avr-gcc-list] JTAG with USB chip FTDI FT2232

[Johnathan Corgan]

Wolfgang Gschwendtner wrote:

> - normal datacommunication via serial UART

Works great!

> - JTAG debugging and programming the flash with the second serial port 
> in the special JTAG mode

I have successfully used the somewhat older FT232BM part in bit bang 
mode to program an ATmega8 via serial download (but not using JTAG.)

> My questions:
> Is there any software that I can use ?

I can't speak to the JTAG mode of the FT2232 part, but I modified 
avrdude to be able to do all its functionality via FTDI bit bang mode 
over the D2XX DLLs on Windows.  There is (experimental!) patch #4330 on 
the tracker at:

http://savannah.nongnu.org/patch/?func=detailitem&item_id=4330

You would need to route 4 pins from the second port of the FT2232 to the 
AVR RESET, MISO, MOSI, and SCK programming pins of the AVR; then the 
patched avrdude could do its thing.  (Note: the patch is for avrdude on 
Cygwin only, I'm working a Linux version.)

Of course, none of this would work using the JTAG port.  I personally 
don't have experience with the FT2232 part (yet) so I can't see if there 
are any hidden gotchas waiting for you.

> has anyone some experience with this Chip together with atmega64 or 
> similar ?

FT232BM <--> ATmega8 USART & SPI works wonderfully.

-Johnathan