Experimental Physics and
Industrial Control System

Florian Feldbauer <[email protected]> · Thu, 23 Oct 2014 08:57:03 +0200

On 10/22/2014 05:49 PM, Scott Baily wrote:

On 10/15/2014 7:11 AM, Florian Feldbauer wrote:

Is it possible (e.g. during initialization) to set the DRVH fields via
the asynPortDriver?

At present asynPortDriver does not set DRVH or DRVL. However, I think

this would be a good addition, and easy to add. AsynPortDriver already

has a getBounds function. If you write your writeInt32 function

correctly, you can have it coerce the value to be within range, and

get the same functionality. Unfortunately, the VAL field of the EPICS

channel won't be coerced so users won't know its happening without a

separate readback channel (but you won't write out of range values to

hardware). The initAi and initAo functions already call getBounds, and

convertAi and convertAo use these limits to calculate eslo and eoff.

I see no reason why initLo and InitAo couldn't be modified to adjust

DRVH and DRVL to these values (i.e. set them if they are both 0, or

adjust them if the current values are out of range). Certainly, one

would want to allow the database to specify a tighter range than

device support permits.

Sure. If the database contains a thighter range than the actual hardware

limit, these limits should not be overwritten by the driver/device support.

I will have a look into the init functions to see how it can be

implemented.

Also, you can probably use less than 17 records for the workaround

others were suggesting if you use a couple of dfanout records.

due to our PV naming scheme I would need a individual macro for each

output link of the dfanout record. Concerning

configuration and maintenance I think using one additional ao record for

each Vset record is easier...

Regards,
Florian

--
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| Dr. Florian Feldbauer                |
|                                      |
| Helmholtz-Institut Mainz /           |
| Johannes Gutenberg-Universität Mainz |
| Johann-Joachim-Becher-Weg 36         |
| D-55128 Mainz                        |
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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System