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Subject: Re: Scan rate '.01 second' not achievable
From: Michael Davidsaver via Tech-talk <tech-talk at aps.anl.gov>
To: Érico Nogueira Rolim <erico.rolim at lnls.br>, "Barrett (US), Patrick E" <patrick.e.barrett at boeing.com>
Cc: "tech-talk at aps.anl.gov" <tech-talk at aps.anl.gov>
Date: Mon, 9 Jan 2023 13:13:15 -0800
On 1/8/23 19:41, Michael Davidsaver wrote:
So the "Scan rate '%s' is not achievable" warning can be ignored.  Almost...

oops.  My mistake.  The timer queue is not used for SCAN.  So this
warning can be ignored in that context.


There is a long standing oddity in the timer queue code where quantum/2 is subtracted from all
user provided delays.  This can result in a negative number, which is treated as 0 delay.

This oddity is relevant in some cases where a record field holds a delay
time.  eg. ODLY of calcoutRecord, or HIGH of boRecord.


References:
Scan rate '.01 second' not achievable Barrett (US), Patrick E via Tech-talk
Re: Scan rate '.01 second' not achievable Érico Nogueira Rolim via Tech-talk
Re: Scan rate '.01 second' not achievable Michael Davidsaver via Tech-talk

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