Experimental Physics and
Industrial Control System

"Davis, Mark via Tech-talk" <[email protected]> · Mon, 21 Oct 2019 18:04:00 +0000

Hi all,

I have a new task that I figured those of you with much more experience 
crafting clever record logic could help with:

The components that need to be supported:

      A record for some device to which setpoints stored in other 
records are to be written (e.g. a motor record).

      A string value that provides a description of the current readback 
of the device record.

      Pairs of numeric and string values.   For each pair, the number 
represents one of the setpoints an operator can chose to have written to 
the device record and the string represents a user-readable description 
of what the associated number represents (e.g. the thickness or type of 
material to place in the path of the beam, the size of a whole in a 
metal plate, etc).

      The operators can change the string (and possibly the numeric) 
values whenever they want.  Changes must be persistent (i.e. changes are 
saved to a file and restored when the IOC restarts, probably using 
autosave).

      Logic that monitors the current readback of the device record. 
Whenever the position is close to (within some specified deadband) of 
the numeric value in one of the numeric/string pairs, it copies the 
associated string to the one that describes the current readback.  When 
the readback is NOT close to one of the numeric values, it will write 
something like "Invalid position" to the description string.

      And of course it has to be relatively simple for the person 
configuring the IOC to change the # of numeric/string pairs supported 
for a device.

No doubt I can cobble something together that will do the job, but I 
figured someone out there will have already dealt with a similar need 
and can provide something much simpler, more flexible, and less 
cumbersome than what I am likely to create on my first attempt.

Any tips or suggestions would be much appreciated.

Thanks,
Mark Davis
NSCL/FRIB

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System