Epics Tips And Tricks And Examples

-- PeterZumbruch - 2017-03-31

Multiple Servers on the Same Host

• Used to not be possible at all (Base 3.13)
• Now, it can be done, but there are problems
• Will get message
  • cas warning: Configured TCP port was unavailable. Using dynamically assigned TCP port 45003, but now two or more servers share the same UDP port. Depending on your IP kernel this server may not be reachable with UDP unicast (a host's IP in EPICS_CA_ADDR_LIST)
• First part means clients will establish their circuit on another port than the default 5064.
  • Not a problem
• Second part means unicast search requests may not get to both servers
  • UDP deficiency, similar to the CaRepeater problem
  • May be a problem when EPICS_CA_ADDR_LIST is used

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<div style="text-align:right;font-size:smaller">EpicsTipsAndTricksCrisAxisAddtionForSeveralEpicsApplications <a href="/edit/Epics/EpicsTipsAndTricksCrisAxisAddtionForSeveralEpicsApplications">(edit)</a></div>

cris-axis addition for several EPICS applications

HOWTO build flex (libfl) for cris-axis crisv32-axis

Since some of the EPICS extensions and modules rely on libfl flex and the standard distribution of AXIS SDK doesn't contain the libfl.a this has to be added:

Prerequisites

• Axis SDK
• cross compiler

Build & Installation

1. set some helper variables:
   export SRC_DIR=<Source Directory>
export DOWNLOAD_DIR=<Download Directory>
# provided cross compiler and SDK are installed here export ETRAX_DIR=<ETRAX Tools Directory>
2. download sources from http://sourceforge.net/projects/flex/ (version 2.5.35) via direct link to $DOWNLOAD_DIR
   mkdir -p ${DOWNLOAD_DIR:?undefined} &&
wget http://prdownloads.sourceforge.net/flex/flex-2.5.35.tar.bz2?download
3. unpack to $SRC_DIR
   mkdir -p ${SRC_DIR:?undefined} &&
cd SRC_DIR &&
tar -jxvf flex-2.5.35.tar.bz
4. Source cris-axis-setup.sh ,defining environment variables, e.g. AXIS_TOP_DIR, and extending PATH, needs ETRAX_DIR to be defined.
   cd ${SRC_DIR:?undefined} &&
wget https://wiki.gsi.de/pub/Epics/EpicsTipsAndTricksCrisAxisAddtionForSeveralEpicsApplications/cris-axis-setup.sh &&
source cris-axis-setup.sh
   or just take its main code:
   oldpwd=$OLDPWD
base=$(pwd)
cd ${ETRAX_DIR:?undefined)/SDK && cd $(ls --color=never -t -1 -d devbo* | head -n 1) && . ./init_env
cd $base
cd ${ETRAX_DIR:?undefined)/ETRAX/compiler && . ./setup.sh
cd $oldpwd
cd $base
unset scriptname base oldpwd epicsDir
5. Change to source directory $SRC_DIR
   cd ${SRC_DIR:?undefined}
6. Since configure automatically sets for cross-compilers 'ac_cv_func_malloc_0_nonnull' and 'ac_cv_func_realloc_0_nonnull' to 'no', (since it cannot check it) those have to be configured by hand:
   1. cris-axis
      1. export myTARGET=cris-axis-linux-gnu
      2. make clean
      3. ./configure --prefix=${AXIS_TOP_DIR:?undefined}/target/${myTARGET:?defined}/usr --host=${myTARGET} --build=i686-pc-linux-gnu ac_cv_func_realloc_0_nonnull=yes ac_cv_func_malloc_0_nonnull=yes
      4. make
      5. make install
   2. crisv32-axis
      1. export myTARGET=crisv32-axis-linux-gnu
      2. make clean
      3. ./configure --prefix=${AXIS_TOP_DIR:?undefined}/target/${myTARGET:?defined}/usr --host=${myTARGET} --build=i686-pc-linux-gnu ac_cv_func_realloc_0_nonnull=yes ac_cv_func_malloc_0_nonnull=yes
      4. make
      5. make install

Compact

export SRC_DIR=<Source Directory>
export DOWNLOAD_DIR=<Download Directory>
# provided cross compiler and SDK are installed here
export ETRAX_DIR=<ETRAX Tools Directory>

mkdir -p ${DOWNLOAD_DIR:?undefined} &&
wget http://prdownloads.sourceforge.net/flex/flex-2.5.35.tar.bz2?download

mkdir -p ${SRC_DIR:?undefined} &&
cd SRC_DIR &&
tar -jxvf flex-2.5.35.tar.bz

oldpwd=$OLDPWD
base=$(pwd)
cd ${ETRAX_DIR:?undefined)/SDK && cd $(ls --color=never -t -1 -d devbo* | head -n 1) && . ./init_env
cd $base
cd ${ETRAX_DIR:?undefined)/ETRAX/compiler && . ./setup.sh
cd $oldpwd
cd $base
unset scriptname base oldpwd epicsDir

# crisv-axis
export myTARGET=cris-axis-linux-gnu
cd ${SRC_DIR:?undefined} &&
make clean
./configure --prefix=${AXIS_TOP_DIR:?undefined}/target/${myTARGET:?defined}/usr --host=${myTARGET} --build=i686-pc-linux-gnu ac_cv_func_realloc_0_nonnull=yes ac_cv_func_malloc_0_nonnull=yes &&
make && make install

# crisv32-axis
export myTARGET=crisv32-axis-linux-gnu
cd ${SRC_DIR:?undefined} &&
make clean
./configure --prefix=${AXIS_TOP_DIR:?undefined}/target/${myTARGET:?defined}/usr --host=${myTARGET} --build=i686-pc-linux-gnu ac_cv_func_realloc_0_nonnull=yes ac_cv_func_malloc_0_nonnull=yes &&
make && make install



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<div style="text-align:right;font-size:smaller">EpicsTipsAndTricksNewIocCommand <a href="/edit/Epics/EpicsTipsAndTricksNewIocCommand">(edit)</a></div>

new IOC command

The general way how to add a new IOC command, which can be used inside the IOC Shell is described in Chapter 18.3 IOC Shell - IOC Shell Programming of the IOC Application Developer's Guide (3.14.9).

Here is an example (with the help of BK) to make the command dumpTable(mbo, dac, channel, type) available at the IOC shell.

• application.c

#include <epicsExport.h>

/* ... */ 

/***************************************************************************/
static void dumpTable(int mbo, int dac, int channel, short type)
{
  /* some function code */
  /* ... */ 
}
/***************************************************************************/

/* Information needed by iocsh */
/* Argument definition */
static const iocshArg  dumpTableArg0 = {"mbo number",     iocshArgInt};
static const iocshArg  dumpTableArg1 = {"dac number",     iocshArgInt};
static const iocshArg  dumpTableArg2 = {"channel number", iocshArgInt};
static const iocshArg  dumpTableArg3 = {"table type",     iocshArgInt};
static const iocshArg  *dumpTableArgs[] = 
{
  &dumpTableArg0,
  &dumpTableArg1,
  &dumpTableArg2,
  &dumpTableArg3
};
/* Function definition */
static const iocshFuncDef dumpTableFuncDef = {"dumpTable", 4, dumpTableArgs};

/* Wrapper called by iocsh, selects the argument types that dumpTable needs */
static void dumpTableCallFunc(const iocshArgBuf *args) {
  dumpTable(args[0].ival, args[1].ival, args[2].ival, args[3].ival);
}

/* Registration routine, runs at startup */
static void dumpTableRegister(void) {
    iocshRegister(&dumpTableFuncDef, dumpTableCallFunc);
}
epicsExportRegistrar(dumpTableRegister);

• application.dbd

variable(mySubDebug)
...
registrar(dumpTableRegister)

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<div style="text-align:right;font-size:smaller">EpicsTipsAndTricksUseOfMsiWithMultipleTempleateFiles <a href="/edit/Epics/EpicsTipsAndTricksUseOfMsiWithMultipleTempleateFiles">(edit)</a></div>

use of msi with multiple template files

To produce a single db file from multiple template files it is sufficient to include in the Makefile in the app/Db directory the line with the name of the db. This should be a not existing file (because it will be produced). Existing must be the corresponding substitutions file and the template file(s). In case that the substitutions file calls to a multiple template files is necessary to have an independent name from them, otherwise the generated db file will be only based on the same name template file.

Be aware that none of the template files should have the same name as the substitutions file.

Example: To make a db called vulom_1.db use a file vulom_1.substitutions which references for instance vulom.template, vulomreg.template, and vulomreg1.template

vulom_1.substitutions:

file vulom.template {
{ PRE=HAD, NN="0", MM="1"}
}
file vulomreg.template {
{ PRE=HAD, NN="0", MM="1", CC="Del_0", AA="0", LIM="49.5", GAIN="3.3", LLIM="0"}
{ PRE=HAD, NN="0", MM="1", CC="Del_1", AA="1", LIM="49.5", GAIN="3.3", LLIM="0"}
}
file vulomreg1.template {
{ PRE=HAD, NN="0", MM="1", CC="Down_0", AA="7", LIM="15", GAIN="1"}
{ PRE=HAD, NN="0", MM="1", CC="Down_1", AA="8", LIM="15", GAIN="1"}
}

The Makefile should contain a line

DB += vulom_1.db

additional Dependencies

Adding the line in the Makefile

vulom_1_DEPENDS ?= $(shell perl -n -e 'if (/file\s+(\w+.template)/) {print "$$1 \n";}' vulom_1.substitutions )

right after the previous

DB += vulom_1.db

enables EPICS to check for dependencies (q.v. IOC Application Developer's Guide - 3.14.9 Chapter 4.6.4):

If a <name> substitutions file contains "file" references to other input files, these referenced files should be made dependencies of the created <name>.db by adding a dependency definition line:
<name>_DEPENDS = <filename1> <filename2> ...

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-- PeterZumbruch - 2017-03-31