Experimental Physics and
Industrial Control System

"Dalesio, Leo" <[email protected]> · Tue, 30 Nov 2004 05:00:07 -0800

All analog output records call the read routine of the driver on initialization. If you are using hardware that maintains its output through a reboot (PLC or a VME card with the sysReset trace cut for instance), and you set the PINI (process record on initiailization) to TRUE, the record should reflect the value in the hardware.

As Bernhard points out - all records are SEVR=INVALID, STAT=UDF, UDF = TRUE. UDF=TRUE indicates that the record has never been processed successfully. Either it has never been scanned or the device support did not exist.

-----Original Message-----
From: Bernhard Kuner [mailto:[email protected]] 
Sent: Tuesday, November 30, 2004 12:09 AM
To: 黄松; [email protected]
Subject: Re: problem about Channel Archiver

Hallo 黄松:

After reboot an EPICS database all records are STAT=INVALID, UDF=1.
First Processing of the record will reset the UDF field to 0 and set STAT to the status that matches the result of the processing - NO_ALARM if no bad things happen. Your ao-record is an OUT record, so it is ok if it is UDF INVALID, as long as nobody wrote something to it.

Another point is to initialize it to a reasonable start value - this is an old EPICS problem, because OUT records have no link field to be initialized after reboot from another record that provides a readback of the hardware. If there is any hardware to readback the "TC:PS:B1:AI1:current" it is Your turn to set your ao-record to this value after reboot of the IOC.

best regards

Bernhard Kuner

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System