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Altera_Forum
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14 years ago

The execution time of software

I am using DE2 device. I have built a SOPC system. Through nios II, I'm trying to create a simple process and send this process to FPGA board. IOWR(PI_Control_BASE,0,0); // Send zero ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

The execution times are reasonably fixed (and determinable) provided that:

1) there is no contention for Avalon slaves

2) there are no delays waiting for anything external (eg JTAD UART)

3) the cache transfers are the same

4) the branch predictor behaves the same way.

To get trully determinable execution times you need to use tightly coupled memory for code and (most) data, and to disable the dynamic branch prediction.