Looking for opinions about open jtag

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I recently got a SAM9Gx5-ek development board and I'm looking for a jtag for it. I'd like one that could also be used for AVR and possibly other types of chips like freescale.

Anybody here have experience with this?

Edit: forgot to add the URL for the project:
http://www.openjtag.org/

Thanks

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JTAG != JTAG. That is, JTAG defines a hardware structure inside the chip, but does not define exactly how to access it. Thus SAM9 JTAG interfaces differently than AVR which is different from TI which is different from (you name it). Atmel is also quite closed about some of the AVR JTAG interface details, if I recall correctly.

Jim

 

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Quote:

if I recall correctly

You do - they document the PC to ICE protocol but not the ICE to AVR protocol which makes it close to impossible for anyone to make clones.

There were clones of the original JTAGICE (which could/can JTAG 10 of the oldest AVR models) but this is simply because they made the schematic available so people copied that then just put a copy of the Atmel firmware in the mega16 ot was based upon. But so far I think only one Chinese company managed to clone the JTAGICEmkII (JTAG to all modern AVRs).

To be honest your cheapest/best bet is simply to pay Atmel $49 for a Dragon and be done with it.

(this will NOT work with ARMs but ARMs can be debugged for $2).

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How do you debug ARMs for $2?

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Google 'wiggler'. If your PC has a parallel port, one ic and a few other bits gives you an open ocd jtag interface that works with just about anything. I've used it to recover wireless routers, dockstars, sam7s .....

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uptime0 wrote:
Anybody here have experience with this?
Bingo created this: Use your STMxx-Discoveryboard as JTAG
ARM9 is in OpenOCD.
AVR - ISP (not OCD) is supported.
Some will do BDM, FPGA, and CPLD.
Another way (by FTDI) is Bus Blaster.

"Dare to be naïve." - Buckminster Fuller