Reply by Martin.J Thompson January 15, 20022002-01-15
Hi Rick,

>I could use some help with a design I am working on. I am using the
>TMS320C6711B along with the MSP430F148 and two Xilinx FPGAs. I would like
>to use all four devices in a single JTAG chain. But I understand that this
>is not a good idea as the different vendor's tools will not work compatibly.

You should be able to set the devices you are not interested in into BYPASS
mode, but the early versions of the C6711 were not JTAG-compliant (according to
the errata sheet)! Who's emulator are you using, they may have different
capabilities - I dunno.

>Is this correct? Will I not be able to use the JTAG debugger on the
>TMS320C6711 and MSP430F148 if I have the Xilinx parts in the chain? I have
>viewed the JTAG documentation available on the TI web site. I still have
>not been able to determine if the JTAG debugger will operate with the
>Xilinx parts in the JTAG chain. I can't even tell if the TMS320C6711 and
>MSP430F148 will be compatible.

I have no idea on this I'm afraid - I wussed out and put our FPGAs on a separate
chain from the DSP!

>I am not so worried about using the Xilinx tools. I don't expect to need to
>use the Xilinx debugger. The Xilinx chips are in the chain for boundary scan.
>BTW, does anyone know how to use the TI emulator as a JTAG controller for
>boundary scan? Is there documentation on that? Has anyone done boundary
>scan before? What did you use as a controller?

Not seen anything on this, but I doubt it. You'll either have to get another
piece of hardware, or if the Xilinx JTAG pod is anything like the Altera
Byteblaster (ie a TTL buffer on the parallel port) you could always write your
own :-)


Martin Thompson BEng(Hons) CEng MIEE
TRW Conekt
Stratford Road, Solihull, B90 4GW. UK
Tel: +44 (0)121-627-3569 -