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Altera_Forum
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15 years ago

Access-duration between reading 2 time from a perepherial

Hi Folks, i implemented a RTC with an resolution of 8 ns with an memory-mapped avalon-interface for reading the timestamps. if i read from this device with nios II/f 2 times, the difference...
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Altera_Forum
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15 years ago

hi Karsten,

in my opinion OS_ENTER_CRITICAL(); disable all interrupts. and the malloc is out of the measurement, only accessing the malloc memory. and my NIOS II run with 100 MHz so there are only 63-72 cycles -> 31 - 37 cycles per read and store.

seems to be a lot of time.

so far

mooresstudent