Enable JTAG fuse without using ISP? (STK500)

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Hello, I just received my JTAGICE mkII and started playing around with it. I am using a ATMega644, which has a JTAG enable fuse bit. Is there a way to enable this fuse bit with the JTAG programmer? The only way I was able to enable this fuse bit was by using ISP.

The reason I want to enable the JTAG fuse bit with the JTAGICE mkII is because I want to build boards in the future with only one programming header. I don't want to make 2 headers, one for ISP to enable the JTAG fuse bit, and the other for JTAG.

When I try to access the ATMega644 with the JTAG fuse bit disabled, it asks me if I want to retry with external reset enabled. I click "yes" and it says "A problem occured when executing the command. See the command output for more info." I could not find where the command output log was located. I also have my reset jumper removed (I tried both ways, neither worked. The manual in AVR studio says to remove the reset jumper though) and the 6 pin ISP cable removed. I was able to program the chip with the JTAGICE mkII after I enabled the JTAG enable fuse with ISP. I am using the Expansion Port 0 on the STK500 with the breakout header board. I verified that Pin 1 on the JTAGICE mkII is connected to pin 1 of the breakout header board.

Thanks for any help!

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As far as I know, every AVR with JTAG comes out of the factory with JTAGEN.

So you never need ISP at all for your production boards.

Bear Murphy's Law in mind for development. It is always handy to have an ISP header because you are quite capable of disabling JTAGEN via JTAG. The equivalent "disable SPIEN via ISP" is NOT possible.

David.

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Oh ok, thanks. Yeah this is an old ATMega644 so I probably disabled the JTAG fuse a long time ago with ISP.