Re: ai - record unfortunately does not behave as I expect it to

[Ralph Lange via Tech-talk <tech-talk at aps.anl.gov>]

The plain "Soft Channel" Device Support does not convert - you would have to write into VAL.

To use RVAL you need to...

• use the "Raw Soft Channel" Device Support that converts
• set the LINR field to select the type of conversion you want. (Probably "SLOPE" in your case.)

Also, CP in an OUT link does not make sense - you need PP to trigger the target.

Cheers,

~Ralph

On Thu, 11 Aug 2022 at 17:01, Heinz Junkes via Tech-talk <tech-talk at aps.anl.gov> wrote:

I probably didn't take something into account, but unfortunately I don't see what I did wrong.

I have modified the ai- record from dbExample1.db:

record(ai, "$(user):aiExample")
{
        field(DESC, "Analog input")
#       field(INP, "$(user):calcExample.VAL  NPP NMS")
        field(ASLO, "2")
        field(EGU, "Counts")
        field(HOPR, "20")
        field(LOPR, "0")
        field(HIHI, "16")
        field(HIGH, "6")
        field(LOW, "4")
        field(LOLO, "2")
        field(HHSV, "MAJOR")
        field(HSV, "MINOR")
        field(LSV, "MINOR")
        field(LLSV, "MAJOR")
}

and write into this record (RVAL) with a calcout record:

record(calcout, "$(user):dummOut") {
  field(INPA, "$(user):calcExample.VAL MS CP")
  field(CALC, "A")
  field(OUT , "$(user):aiExample.RVAL CP")
}

RVAL is also changed, but VAL remains 0:

(base) hactar:iocmyExample junkes$ camonitor junkes:aiExample.RVAL junkes:aiExample.VAL junkes:aiExample.ASLO
junkes:aiExample.RVAL          2022-08-11 16:52:57.014817 2 LOLO MAJOR
junkes:aiExample.VAL           2022-08-11 16:52:57.014817 0 LOLO MAJOR
junkes:aiExample.ASLO          2022-08-11 16:52:57.014817 2 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:52:58.016001 3 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:52:59.017708 4 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:53:00.015190 5 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:53:01.017940 6 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:53:02.015414 7 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:53:03.018187 8 LOLO MAJOR
junkes:aiExample.RVAL          2022-08-11 16:53:04.018058 9 LOLO MAJOR

In the record reference manual :

If the device support sets the RVAL field, the LINR field controls how this gets converted into engineering units and placed in the VAL field as follows:

1. RVAL is converted to a double and ROFF is added to it.
2. If ASLO is non-zero the value is multiplied by ASLO.
3. AOFF is added.

Danke,  for taking a look,
Heinz