Experimental Physics and
Industrial Control System

Marty Kraimer <[email protected]> · Tue, 12 Jul 2005 06:41:57 -0500

Benjamin Franksen wrote:

On Monday 11 July 2005 14:55, Marty Kraimer wrote:

Also templates should not appear in the DBD files. This can be done
by properly defining interfaces which are implemented by "record
fragment".

Hmm. Can you explain how, for instance, an 'invalidOutput' struct can be

specified in the DBD so that it is usable as building block for

stringout as well as ao record type, without parameterizing over the

type of the value?

I did not express myself properly.

It is not the templates but the methods that should not appear in the

DBD files.

There should not be ANY language specific definitions in DBD or DB
files.

Note, in my original proposal (on the wiki), there is not a single

mentioning of a C or C++ language feature in the DBD file. If you

insist, I can write down a precise and self-contained definition of the

meaning of the angle-brackets notation I used in the DBD fragments I

posted.

Ben

The following shows a way to handle code fragments just like device support.

1)NO METHODS appear in the dbd file.
2) It uses Andrew's suggestet syntax for templates.
3) It uses a device definition

A dbd file contains the following:

menu(invalidAction) {
   choice(invalidActionContinue_normally,"Continue normally")
   choice(invalidActionDon_t_drive_outputs,"Don't drive outputs")
   choice(invalidActionSet_output_to_IVOV,"Set output to IVOV")
}

The record.dbd file contains

record(xxx)  extends iocRecord {
   ...
   field(invalidAction,menu(menuIvoa))
   field(outputValue,float64)
   field(invalidOutput,device(none,processInvalidOutput))
   ...
}

Also in a dbd file the following appears
   device(none,default,processInvalidOutput)

Some .h file contains:

   class processInvalidOutput {

 virtual void compute(int32 value, DbfMenu &invalid,epicsString

&status, epicsInt16 &severity);

 virtual void compute(float64 value, DbfMenu

&invalid,epicsString &status, epicsInt16 &severity);

         ... // perhaps other types for value
   }

The process routine then has a statement like

pprocessInvalidOutput->compute(outputValue,invalidOutput,,status,severity);

Thus code fragments are handled just like device suppoort that has no

direction.

For this example the device definition also has no dataStructName. Code

fragments that need additional private data could define a dataStructname.

Marty

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System