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Entry  14 Jan 2004, Razvan Stefan Gornea, , Access to hardware in the MIDAS framework 
    Reply  14 Jan 2004, Stefan Ritt, , Access to hardware in the MIDAS framework 
       Reply  16 Jan 2004, Razvan Stefan Gornea, , Access to hardware in the MIDAS framework frontend.cmeterdev.c
          Reply  17 Jan 2004, Stefan Ritt, , Access to hardware in the MIDAS framework 
Message ID: 8     Entry time: 17 Jan 2004     In reply to: 7
Author: Stefan Ritt 
Topic:  
Subject: Access to hardware in the MIDAS framework 
> The result is strange because the get function is called all the time very 
> fast (much faster then the 9 seconds as set in the equipment) and even 
> before starting the run (I just put the flag RO_RUNNING).

This is on purpose. When the frontend is idle, it loops over the slow control 
equipment as fast as possible. This way, you see changes in your hardware very 
quickly. I see no reason to waste CPU cycles in the frontend when there are 
better things to do like reading slow control equipment. Presume you have the 
alarm system running, which turns off some equipment in case of an over 
current. You better do this as quickly as possible, not wasting up to 9 
seconds each time.

The 9 seconds you mention are for reading *EVENTS*. You have double 
functionality: First, reading the slow control system, writing updated values 
to the ODB, where someone else can display or evaluate them (in the alarm 
system for example). Second, assemble events and sending them with the other 
data to disk or tape. Only the second one gets controlled by RO_RUNNING and 
the 9 seconds. You can see this by the updating event statists on your 
frontend display, which increments only when running and then every 9 seconds.
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