Re: StreamDevice reading waveforms

[Dirk Zimoch <dirk.zimoch@psi.ch>]

Hello Anthony,

For waveform records StreamDevice repeats the format for each element 
and optionally reads a separator in between. While this allows to read a 
row, it cannot read a column. And it probably does not work with 
redirection (I have never tried).
This makes it a bit complicated to read your device. But hopefully not 
impossible. You need a few more records.
I understand that the reply always consists of 3 rows. Then I would try 
the following:
Have two longin records, one for X and one for X.
Redirect to these records as you do now, but do it 3 times:

Terminator = "\n";
getTBT_XY {
    out "TBT_XY 3";
    in   " %(\$1TBT_Horizontal_tmp)d %(\$1TBT_Vertical_tmp)d";
    in   " %(\$1TBT_Horizontal_tmp)d %(\$1TBT_Vertical_tmp)d";
    in   " %(\$1TBT_Horizontal_tmp)d %(\$1TBT_Vertical_tmp)d";
}

This processes the two longin records 3 time each. For the waveforms use 
two compress records and do a FLNK from the longin records to the 
compress records:
record (longin, "$(P)$(R)TBT_Horizontal_tmp")
{
   field (FNLK, "$(P)$(R)TBT_Horizontal")
}

record (compress, "$(P)$(R)TBT_Horizontal")
{
   field (INP,"$(P)$(R)TBT_Horizontal_tmp")
   field (ALG, "Circular Buffer")
   field (NSAM,"3")
}

The same for Vertical.

I am not quire sure about the compress record settings. Maybe you need 
to try a bit.
Maybe you may want to write to the .RES of the compress before starting. 
In that case you can use additional seq records.
Hope this helps.

Dirk

On 09.04.2015 23:01, Anthony Pietryla wrote:
> I have a device which uses SCPI protocol and returns sets of waveforms
> in columns where I can request how many rows to return. For instance I
> can query the device for 3 values of position data and it will return 2
> columns (X & Y) and 3 rows. I want to read the columns into separate
> waveform records. I am having problems with the protocol file for which
> I need help.
>
> The database records and the protocol file are listed below. When I
> process the record only the first values (first row of data) are written
> to each record. With asyn debugging turned on the console shows all
> three sets of data:
>
> epics> 2015/04/09 13:52:36.877 L0 wrote
> TBT_XY 3
>
> 2015/04/09 13:52:36.878 L0 read
>    2000   6000
>    7143   4286
>    4286   1429
>
> caget shows only the first value stored:
>
> caget -# 5 B:Spark:TBT_Horizontal
> B:Spark:TBT_Horizontal 5 3333 0 0 0 0
>
> caget -# 5 B:Spark:TBT_Vertical
> B:Spark:TBT_Vertical 5 -1111 -3333 0 0 0
>
> *******************
> The protocol file has:
>
> getTBT_XY {
>     Separator = "\n";
>     out "TBT_XY 3";
>     in   " %(\$1TBT_Horizontal)d %(\$1TBT_Vertical)d";
>     ExtraInput = Ignore;
> }
>
> **************
> The database records are:
>
> record(waveform, "$(P)$(R)TBT_Horizontal")
> {
>     field(DESC, "TBT Horizontal")
>     field(DTYP, "stream")
>     field(INP,  "@spark.proto getTBT_XY($(P)$(R)) $(PORT)")
>     field(NELM, "262144")
>     field(EGU,  "um")
>     field(FTVL, "LONG")
> }
>
> record(waveform, "$(P)$(R)TBT_Vertical")
> {
>     field(DESC, "TBT Vertical")
>     field(DTYP, "Soft Channel")
>     field(NELM, "262144")
>     field(EGU,  "um")
>     field(FTVL, "LONG")
> }
>
> ********************
> When I comment out the “ExtraInput = Ignore;” line in the protocol file
> I get error messages:
>
> 2015/04/09 15:53:58.170 L0 wrote
> TBT_XY 3
>
> 2015/04/09 15:53:58.170 L0 asynOctetBase interrupt
> 2015/04/09 15:53:58.171 L0 read
>    3333  -1111
>   -3333  -5556
>   -2000      0
>
> 2015/04/09 15:53:58.271 L0 B:Spark:TBT_Horizontal: 29 bytes surplus
> input "<0a> -3333  -5556<0a> -200..."
> 2015/04/09 15:53:58.271 L0 B:Spark:TBT_Horizontal: after 13 bytes:
> "  3333  -1111"
>
> caget -# 5 B:Spark:TBT_Horizontal
> B:Spark:TBT_Horizontal 5 3333 0 0 0 0
>
> caget -# 5 B:Spark:TBT_Vertical
> B:Spark:TBT_Vertical 5 -1111 -3333 0 0 0
>
>
> --
> Anthony Pietryla
> Principal Controls Engineer
> Advanced Photon Source
> Argonne National Laboratory
>
> Phone: 630-252-7430
> Fax: 630-252-6123