Experimental Physics and
Industrial Control System

Mark Rivers <[email protected]> · Wed, 9 May 2018 17:19:31 +0000

Hi Konrad,

I suggest you create an issue in asyn on Github.

My questions:

Would we use the existing asynMask syntax but change "mask" to be something like 0x0F0;8  where the bits before the ; are the mask and the bits after are the shift?
field(INP,"@asynMask(portName,addr,mask,timeout)drvParams")

Or do we make a new asynMaskShift syntax like this?
field(INP,"@asynMaskShift(portName,addr,mask,shift,timeout)drvParams")

Would this apply to longin and longout records?  Any other records that should support this syntax?

For longin first the mask is done in the driver and then the shift is done in device support?

For longout first the shift is done in device support and then the mask is done in the driver?

Is this a common enough use case to justify the change? 

Mark

-----Original Message-----
From: Konrad, Martin [mailto:[email protected]] 
Sent: Wednesday, May 9, 2018 8:02 AM
To: Mark Rivers <[email protected]>
Cc: EPICS Tech Talk <[email protected]>
Subject: devAsynUInt32Digital: add parameter for shifting?

Hi Mark,
devAsynUInt32Digital currently supports the following parameters:

field(INP,"@asynMask(portName,addr,mask,timeout)drvParams")

We are reading out a bunch of 32 bit registers containing smaller numbers like 4x 8 bit. The mask allows us to pick a subset of bits but the generic device support doesn't seem to allow us to shift them. To make that happen we are currently using an additional calc record. I'm wondering if this use case is common enough to justify adding another parameter for shifting?

-Martin

--
Martin Konrad
High Performance Controls Team Leader
Facility for Rare Isotope Beams
Michigan State University
640 South Shaw Lane
East Lansing, MI 48824-1321, USA
Tel. 517-908-7253
Email: [email protected]

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System