Experimental Physics and
Industrial Control System

"Hartman, Steven M." <[email protected]> · Wed, 4 Apr 2012 14:11:40 -0400

On Apr 4, 2012, at 12:43 PM, Pavel Masloff wrote:
> You are right - I want the record to automatically switch its value back to 0 after somebody sets it to 1. Time doesn't really matter. Imagine a pneumatic valve. I have two records two control it: cmd:valve_ON and cmd:valve_OFF.

That is a typical use of the HIGH field of a bo record. 

> Steve, do you recommend to change the SCAN field to passive?

Setting SCAN to passive means it should process when the record VAL field is written to (such as when you click the button on the operator interface screen to set VAL to 1), and then process again after HIGH seconds to reset to 0. Setting SCAN to I/O intr means you are expecting the hardware to generate an interrupt to signal the record when it is time to process. 

Given your description of the record's function, passive sounds appropriate.

-- 
Steven Hartman
[email protected]

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System