Experimental Physics and
Industrial Control System

Dirk Zimoch <[email protected]> · Mon, 13 Aug 2018 13:39:11 +0200

On 13.08.2018 13:12, Ralph Lange wrote:

If I remember correctly,

the epics-modules/stream does not require you to run configure in the

pcre directory.

Have you tried just building it?

Exactly. The EPICS Makefile replaces the ./configure stuff.

If you have PCRE already installed on your system, you should not need

to build it. PCRE should be available for all Linux systems and for

Windows as well. Install the development package (the once with the

header files).

For example, I have this for my Linux system:
$ rpm -qa | grep pcre
pcre-devel-7.8-7.el6.i686
pcre-devel-7.8-7.el6.x86_64
pcre-7.8-7.el6.x86_64
pcre-7.8-7.el6.i686

Cheers,
~Ralph

On Mon, 13 Aug 2018 at 12:17, Abdalla Ahmad <[email protected]

<mailto:[email protected]>> wrote:

    Hello Dirk

    No the device does not echo any command.

    I downloaded the latest stream device from github but It needs PCRE,
    which I got from epics-modules/stream , I took the folder "pcre",
    did "./configure" and make and I get the error

    No rule to make target doc/html/NON-AUTOTOOL-Build.txt needed by all-am.

    Could there be an option to pass to the configure script do disable
    doc files? Or maybe I got PCRE module? There is a yum package
    installed called pcre so I added the libraries to ldconfig but still
    I get undefined reference errors.

    Best Regards,
    Abdalla.

    -----Original Message-----
    From: Dirk Zimoch [mailto:[email protected]
    <mailto:[email protected]>]
    Sent: Monday, August 13, 2018 1:05 PM
    To: Abdalla Ahmad <[email protected]
    <mailto:[email protected]>>; [email protected]
    <mailto:[email protected]>
    Subject: Re: Parse a variable-length, multi-column waveform in
    stream device

    On 13.08.2018 11:33, Abdalla  Ahmad wrote:
     > Hello Dirk
     >
     > That is really impressive, thank you very much. I will integrate
    your protocol in the IOC and provide you with feedback.
     > Regarding your assumptions:
     > 1. We used the LF terminator with setpoints and readings and it
    works fine so I suppose that is the correct terminator.
     > 2. Will this work with variable buffer length? I mean instead of
    "3" for example we pass the PV for buffer length.

    Yes. Just make sure that NELM is big enough for your longest
    possible reply.

     > 3. Since the rest are passive scan, If I understand correctly
    processing the first one will process the others right?

    The input from the first one will make the "I/O Intr" records process.
    However, any input from any other record will be given to the "I/O
    Intr"
    records. Thus if you have other data that matches the format, those
    records will be processed falsely.

    Does the device echo the command "TBT_IQ <n>"? If not, there is no
    way for the "I/O Intr" records to find out if they should parse
    input or not. Thus they will try to parse everything and if they
    succeed, they will process the record.

     >
     > Best Regards,
     > Abdalla.
     >
     > -----Original Message-----
     > From: Dirk Zimoch [mailto:[email protected]
    <mailto:[email protected]>]
     > Sent: Monday, August 13, 2018 12:15 PM
     > To: Abdalla Ahmad <[email protected]
    <mailto:[email protected]>>; [email protected]
    <mailto:[email protected]>
     > Subject: Re: Parse a variable-length, multi-column waveform in
    stream device
     >
     > Hello Ahmad,
     >
     > I have tested a solution using regexp to isolate the columns. But
    while doing that I found a bug in the regexp converter. Thus to make
    it work you need to use the latest commit from
    [email protected]:paulscherrerinstitute/StreamDevice.git
     >
     > What I do is the following:
     > 8 waveform records read the 8 columns. One is active, the other 7
    read the data with "I/O Intr".
     >
     > 8 protocols use regsub (%#/regexp/subst/) to remove the 7 values
    not needed for each waveform.
     >
     > Process waveform 1 and all 8 will get their column.
     >
     > I had to assume some details, e.g. line terminator "\n" and space
    after each value, including the last column. If that is wrong, the
    protocols need to me modified a bit.
     >
     > As I can't see any special marker for the last line, I do NOT use
    an InTerminator, because I need to read the whole table as one
    string. In case there is a marker, e.g. an empty line, you may set
    inTerminator accordingly ("\n\n") and remove the "\n" at the end of
    the 'in' commands.
     >
     > See attached files.
     >
     > Dirk
     >
     >
     > On 12.08.2018 08:22, Abdalla  Ahmad wrote:
     >> Hello Dirk
     >>
     >> Thank you for your reply, looking forward for your results. I
    would like to point out some notes:
     >> 1. Regarding variable size, you can expect for sure way larger
    buffer sizes than 1000.
     >> 2. Why the protocol parse you mentioned won't work? I may have
    understood you wrong but In a single line you can parse any number
    you want by skipping the others and I managed to do that by the same
    format you provided. The first "%i" will get the first number. But
    the problem is if I don't use "ExtraInput = Ignore" the IOC shell
    will be flooded with "x bytes surplus input" error.
     >> 3. Will you implement new parser in stream device to parse
    interlaced arrays? After many trials with stream device, it's either
    this or to develop a new EPICS driver for the device.
     >>
     >> Best Regards,
     >> Abdalla
     >>
     >> -----Original Message-----
     >> From: Dirk Zimoch [mailto:[email protected]
    <mailto:[email protected]>]
     >> Sent: Wednesday, August 08, 2018 12:37 PM
     >> To: Abdalla Ahmad <[email protected]
    <mailto:[email protected]>>; [email protected]
    <mailto:[email protected]>
     >> Subject: Re: Parse a variable-length, multi-column waveform in
    stream
     >> device
     >>
     >> Hello Ahmad,
     >>
     >> StreamDevice can read variable length arrays. You need to set
    NELM to the maximum number of elements. StreamDevice will set NORD
    to the number of elements found. Modern EPICS versions are able to
    handle variable length arrays when the client sets up a monitor
    using 0 for the requested array length. It should then use the
    current NORD value.
     >>
     >> However StreamDevice reads arrays in rows, not columns. If you
    have a waveform record and use { separator=" "; in "%i"; }, stream
    device will repeat the "%i" up to NELM times (or until end of line,
    until the separator is not found any more or until the conversion
    fails).
     >>
     >> But in your case it seems you have interlaced arrays:
     >>
     >> a[0] b[0] c[0] d[0] e[0] f[0] g[0] h[0] a[1] b[1] c[1] d[1] e[1]
    f[1]
     >> g[1] h[1] a[2] b[2] c[2] d[2] e[2] f[2] g[2] h[2]
     >>
     >> So StreamDevice will see the first elements of each array, not
    all elements of one array.
     >> StreamDevice would be able to read rows with variable length:
     >>
     >> a[0] a[1] a[2] ...
     >> b[0] b[1] b[2] ...
     >> c[0] c[1] c[2] ...
     >> d[0] d[1] d[2] ...
     >> e[0] e[1] e[2] ...
     >> f[0] f[1] f[2] ...
     >> g[0] g[1] g[2] ...
     >> h[0] h[1] h[2] ...
     >>
     >> Also this will not help:
     >> in "%i %*i %*i %*i %*i %*i %*i %*i";
     >> Because the first %i reads all the elements in the row before
    even parsing the first %*i.
     >>
     >> I need a new syntax to specify interlaces arrays.
     >>
     >> The only way I can think to at the moment is to pre-process the
    input with a regsub which removed the "other" array elements from
    the input, but I need to test that first. It may be quite
    inefficient. Thus if <N> becomes huge (say >1000) parsing may be
    quite slow.
     >>
     >> I will tell you soon if I can find a solution...
     >>
     >> Dirk
     >>
     >>
     >> On 08.08.2018 11:09, Abdalla  Ahmad wrote:
     >>> Hi
     >>>
     >>> We are trying to implement an IOC for the Libera Spark BPM using
     >>> stream device, one of the tricky commands for example is TBT_IQ <N>
     >>> which returns a variable-length buffer of turn-by-turn data. An
    example:
     >>>
     >>> TBT_IQ 3
     >>>
     >>> 22 -36  19 -38  16 -31  -3  -31
     >>>
     >>> 39 -212 29 -212 26 -163 -37 -150
     >>>
     >>> 39 -175 36 -176 27 -133 -21 -129
     >>>
     >>> As you can see the output is an array of fixed columns (IQ
     >>> parameters) and variable rows (waveforms length). In a single line
     >>> you can easily parse and skip any value, but in this format we
    have two problems:
     >>>
     >>> 1.Is it possible to parse variable number of IN commands in the
     >>> protocol file?
     >>>
     >>> 2.Variable "IN" commands mean variable waveform length, is this
     >>> possible in EPICS?
     >>>
     >>> Best Regards,
     >>>
     >>> Abdalla Ahmad
     >>>
     >>> Control Engineer
     >>>
     >>> SESAME
     >>>
     >>> Allan, Jordan.
     >>>
     >>> Tel: (+962-5) 3511348 , ext. 265
     >>>
     >>> Fax: (+962-5) 3511423
     >>>
     >>> Mob: (+962-7)88183296
     >>>
     >>> www.sesame.org.jo <http://www.sesame.org.jo>
    <http://www.sesame.org.jo/>
     >>>

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System