Experimental Physics and
Industrial Control System

"Allison, Stephanie" <[email protected]> · Fri, 10 Dec 2004 10:44:36 -0800

Hi Steve,

> I am interested in knowing what techniques other people in 
> other facilities use to initialise the values of their output records so that 
> they match the state of the equipment when the IOC is rebooted.  

There are three flavors of output record initialization that we use:

(1) For records where we want the device to always come back to the same, predefined value (no matter what was being done before the IOC reboot), we set the predefined value in the DOL field and set PINI to YES.  We do this for certain settings on delay generators and stepper motors that are not changed often and can only be changed by a diagnostic engineer who is aware of the need to change the .db file if s/he wants the change to be permanent.  The "only be changed by" could be enforced by channel access security but we normally just use a diagnostic EDM display or probe.

(2) For records that have readback available and initialization device support, the setpoint is set to the readback by device support at the proper time in iocInit.

(3) For records that either:
	(a) don't have readback
	(b) don't have proper device support initialization
	(c) are soft
	(d) are used to calculate a device setpoint and there is no back-calculation from the device setpoint back to the higher-level value
we use one of the bumpless reboot restore facilities.  In our case, we get the setpoints either before iocInit or before any record processing by iocInit from a server which gets the values from our RDB.  The setpoints are restored using static database access.   For these records, we do NOT set DOL (won't work if you do) but we do set PINI to YES.

Stephanie Allison

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System