Re: [AVaRICE-user] AVR Dragon not working with atxmega16d4

[Element G. <el...@el...>]

Hello Joerg,

On Tue, Oct 20, 2015 at 9:35 AM, Joerg Wunsch <j...@ur...> wrote:

> As Element Green wrote:
>
> > Thank you for your reply.  I downgraded the firmware to 7.21 (from AVR
> > Studio 5).
>
> I just upgraded another Dragon to 7.38 (decimal), and it works without
> troubles using AVaRICE (SVN version) on my ATxmega16D4 board.
>
>

Good to hear that it's not related to the version.



> > I attempted to use the Dragon to connect to 2 different XMEGA devices,
> one
> > is a custom PCB I made with an xmega16d4, the other is a development
> board
> > with an xmega128d4 using AVR Studio 7 in programming mode.  It could read
> > the reference voltage but not the device ID.
>
> That somehow smells like connection issues on the PDI level.
>
> The target voltage is sensed on the Dragon itself, without the need
> for a working PDI link.  This error code 0xAE is likely an indication
> for PDI link issues - but still, you might ask Atmel explicitly about
> that.  While the JTAGICEmkII protocol is officially documented in an
> appnote, the Xmega protocol isn't.
>
> How long's your cable?  The levelshifters/drivers on the Dragon are
> known to be fairly weak.  In general, the cables that come with an STK500
> work well, they are about 15 cm long.  Anything longer might cause
> troubles.
>


I had that thought as well about the cable length after reading something
to that effect on a forum post.  My guess is that that is the issue now
that you mention it again, though I got sidetracked by the thought that it
was a version incompatibility.  The cable I have came with a ZeptoProg II
programmer and is probably about 10 inches long.  I'll get some shorter
ones and see if that makes a difference.  Perhaps the 0xAE code can be used
to identify cable length issues.  Guess I will see.



> --
> cheers, Joerg               .-.-.   --... ...--   -.. .  DL8DTL
>
>

Cheers!

Element Green