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By Stevetronics
Hey all, I've got a project in the works that needs to program a CPLD (in this case an ATF1508ASVL in the 84PLCC package from atmel) and I was wondering if the JTAG interface on the ATmega128 would be useable for this, or if it is solely a programming interface. Any help would be great. Thanks!
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By leon_heller
The JTAG I/F is just for programming and debugging.
By Polux rsv
If I remember correctly, JTAG is a kind of SPI: clock, data in, data out and some control signal. You could probably use the SPI and some IO lines.