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Altera_Forum
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12 years ago

How to craete a 1 microsecond interval Timer of HPS ?

What HWLIB APIs should I use to configure a Timer of HPS with a 1 micro-second interval ? How can I get the Timer Input Clock frequency and set the appropriate count into Timer ? Than...
Altera_Forum's avatar
Altera_Forum
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12 years ago

May be errors in forum engine -- I see all 3 pictures, refresh htis page and in small popup window see:

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6.5 us may be decreased if modyfy CFLAGS in Makefile from -O0 (Debug) to -O3 or -Ot (if present such key for time optimisation). On Release compiler must generate much faster code for Altera-s interrupts global handler in alt-interrupt.c and yours with LED blinking.

If slow code, many interrupt demands glues to one in waiting for service if serviced previous pack, system not run good code, stay cyclic in interrupt handler.

May go to Disassebbler window and step there all way of executing and sum all ASM commands in both variants, -O0 and -O3.

I reads books about Windows device drivers system, there described that Windows may process 2-3 thousand of interrupts per second: very complicated mechanism of processing with many filters.