Hi,

It might be a naive question, however, I just want to make sure. Is
Xilinx new USB JTAG backward-compatible with old parallel port JTAG
development boards? I'm a bit suspicious as some of the newer Xilinx
boards say explicitly that the board is compatible with the USB JTAG. I
know a JTAG is a JTAG regardless of whether it's USB or parallel port
based. Just want to make sure. Please I would be grateful if anybody
can clear this out for me as I need to order some stuff.

Thanks in advance,
Cheers,

Manny wrote:
> Hi,
> 
> It might be a naive question, however, I just want to make sure. Is
> Xilinx new USB JTAG backward-compatible with old parallel port JTAG
> development boards?
The programming is done via JTAG, which is an IEEE standard. Both the
USB-cable as well as the old parallel cable use JTAG to talk to the
device. So yes, you can use the USB cable for all boards with a JTAG
connector.

But you need to make sure to use a recent version of ISE. iMPACT doesn't
support the USB cable before the 7.1i release, I think.

cu,
Sean

Sean,

Thanks a lot. I know JTAG is an IEE standard. I just wanted to be 100%
sure.

Thanks again,
Cheers,
-Manny

Manny wrote:
> It might be a naive question, however, I just want to make sure. Is
> Xilinx new USB JTAG backward-compatible with old parallel port JTAG
> development boards? I'm a bit suspicious as some of the newer Xilinx
> boards say explicitly that the board is compatible with the USB JTAG.

Perhaps you are referring to the Spartan 3E starter kit?

In this case, in addition to the 6 pin JTAG header, it has a USB
connector (and USB chip) on board so you can program it without having
to buy *any* programming cable at all.

Alan Nishioka