Experimental Physics and
Industrial Control System

"Leblanc, Gregory via Tech-talk" <tech-talk at aps.anl.gov> · Thu, 11 May 2023 21:42:48 +0000

Hi folks,

I've finally gotten EPICS chatting reasonably with my Keysight 34980A mainframes, both to read data through one of the MUX cards, and now to output voltages through the DAC.  My next step is to start building some interfaces.  Reading in and graphing some data trends went quite well using the examples and modifying them to use PVA://myPVname.  I'm having more trouble getting output sent out to my PVs.

I started with the "Incremental Controls"/spinner slider scrollbar and looked at modifying the scaled slider horizontal widget.  I modified it to use PVA://KS_34980A_EPICStestwriteOutput1 and adjusted the values to go from 0 to 16 in 0.1 increments, and turned off the hi/lo labels.  However, when I try to drag the slider, it pops back to 0 immediately when I release the mouse button.    Using the keyboard makes the slider move but doesn't change the PV.  

I can write to that PV using 'pvput KS_34980A_EPICStestwriteOutput1 #' and see that it does indeed update, so I think I must be doing something wrong in Phoebus.  I've attached my slider.bob file.  The record that I'm writing to looks like: 

record(ao, "$(P)$(R)writeOutput1") {
    field(DESC, "Write to Test Output 1")
    field(DTYP, "stream")
    field(PREC, "3")
    field(EGU,  "Volts")
    field(SCAN, "Passive")
    field(OUT, "@devKS_34980A_EPICS.proto setSourceVoltage(%E,2001) $(PORT) $(A)" )
    field(PINI, "YES")
    field(VAL, "0")
    field(FLNK, "$(P)$(R)readOutput1")
}

Any pointers are greatly appreciated, 
     Greg

--
Gregory Leblanc
Accelerator Engineer
Edwards Accelerator Lab - Ohio University
123 University Terrace
Athens, OH 45701 USA
leblanc at ohio.edu
M: (401) 52-OUAL1 or (401) 526-8251

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System