JTAG Connections

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Is there a standard 10-pin to 6-pin adaptor cable available from Atmel (or anyone else) that has all the JTAG signals (TMS, TCK, TDI, TDO, GND, VT)? The 6-pin ISP adaptor cable does not have TMS connected.

I know we can make one up special. But it would be nice if there is something off-the-shelf for our clients.

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six pins are not enough to connect the jtag. You also need the reset line. I've seen 8 pin connectors used for the Atmel Jtag, 6 pins are only enough for ISP, PDI, or debug wire.

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Thanks for the comment but I believe that as long as the JTD bit in MCUCSR is not set by the firmware (not sure why we would do that) RESET is not required. (See the JTAGICE mkII Quick Start Guide page 3.)

Unfortunately we are modifying an existing PCB and a 10-pin connector may not fit without rerouting much of the board to make room.

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Quote:
not sure why we would do that
So that you can use the JTAG pins for other purposes at run time? No problem if they are not used for anything else.

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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you can always fit in a connector with tighter pitch to get in the required number of connections. Instead of .1" spacing pitch you could use a connector with a pitch of 1, 1.5 or 2mm to fit in the required number of contacts. You are going to have to make an adapter cable anyway.