Messages in this thread |  | | Date | Fri, 01 Sep 2000 15:40:45 +0200 | From | Peter Mueller <> | Subject | Strange behaviour of a cyclic task with HZ = 1024 |
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Hi,
I have set the HZ constant to 1024 to increase the select resulution. But the results of my measurements are not as expected. I have a cyclical task (using select for timing) that inverts a parallel port bit in each cycle. I measure the high time with an oszillograph.
Here are my results:
15ms cycle: Everything as expected. The jitter is around 1ms (corresponds to the 1000Hz). 10ms cycle: The cycle is either 10ms or 20ms. No values between. 5ms cycle: The cycle is either 10ms or 15ms. No values between.
Do you have any explanations for this behaviour? Is there a better way to increase to resolution of the select call?
Peter
P.S: I found that the HZ constant is used in the tcp code. Do I have to expect any errors coming from the changed HZ value?
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