in the past I had a separate crystal for the Mega32 CPU and for a SPI to serial converter (MAX3100). Usage of Jtag ICE was as expected.
To simplify the board the CPU crystal was replaced by a wire from the Mega clock-input to the MAX clock output. While the programm was not changed a reload was not necessary. The application was running perfectly.
Now with the external clock a program improvement was required. The results were:
- loading of the programm via Jtag does not lead to a running application (AVRSTudion showed only FFFF in the assembly window).
- Stopping did not work immediately, only after ten or twenty seconds and single stepping did not work either.
-Single stepping looked like debugging of a optimized code - jumping without a logical sequence through the source code.
I tried to change the clock fuses from external high speed crystal to external clock (can't remeber which delay) without any progress.