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Altera_Forum's avatar
Altera_Forum
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19 years ago

NIOS II Perfromance

Does anyone know what the read and write cycle performace of NIOS II to external / Internal devices. I am especially interested in the number of clocks required between single access and multiple - b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
19 years ago

There really is not a hard answer to this. It depends a lot on how your code is written and the peripheral that you are interfacing to. The NIOS II processor reference indicates that any load or store insruction should take 1 clock cycle if it does not involve an Avalon transfer but >1 if it does involve an avalon transfer. Not very informative.

My personal experience with reading data from an avalon peripheral and storing the data into an array in memory while viewing the transfers on the oscilloscope is 3 clocks per transfer. But again this depends on the implementation.