Re: JTAG multiple devices

On Aug 25, 7:29 pm, Anton Erasmus <nob...@xxxxxxxxxxxxxxxx> wrote:
On Fri, 24 Aug 2007 10:56:58 -0700, linnix <m...@xxxxxxxxxxxxxxxxxx>
wrote:

[Snipped]

Following Atmel specs, we could SPI program the AVR and JTAG boundary
scan them. We are unable to do JTAG programming as stated in the AVR
specs. So, we end up with both interfaces on every production board.

I have had no problem programming Atmel devices using the JTAG
interface. I use an altera byteblaster and my own software.

Good to know that it could work. I might get back to it later. For
now, ISP works fine for us. However, it would simplify our interfaces
if we can do everything in JTAG.

AFAIK there is some sort of issue if the AVR is not the only device on
the chain, but IIRC it stops one accessing the other devices, and not
the AVR itself.

Regards
Anton Erasmus


.

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