IOC Utilities

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The utilities comprise of useful IOC db templates and IOC shell utilities.

DB Templates

Below are available utility templates for substitution. In order to allow Make to build these, you need to add the following to your Device/master/configure/RELEASE file: UTILITIES=$(SUPPORT)/utilities/master.

Field setter

This copies the specified field from a PV and sets it on a different PV. E.g.

file $(UTILITIES)/db/field_setter.template { 
  pattern 
    {P,    FROM, TO, FIELD}

    {"\$(P)", "UNITS", "READING", "EGU"}
    {"\$(P)", "UNITS", "SP", "EGU"}

}

This example copies the EGU field from $(P)READING to $(P)UNITS.EGU and $(P)SP.EGU.

Unit setter

This copies units from a PV and sets them on a different PV. E.g.

file $(UTILITIES)/db/unit_setter.template { 
  pattern 
    {P,    FROM, TO}

    {"\$(P)", "UNITS", "READING"}
    {"\$(P)", "UNITS", "SP"}

}

This will copy units from the value of the PV $(P)UNITS to $(P)READING and $(P)SP.

Error Setting

Creates a raw PV that can be written to by a stream protocol and then transfer the stream protocols PV error and value to the real PV.

For example:

file $(UTILITIES)/db/error_setter.template {
    pattern {P, STREAM_PV, PV_NAME}

    {"\$(P)", "UNITS", "READING"}
    {"\$(P)", "UNITS", "SP"}

}

The error setter creates intermidate PVs named $(PV_NAME):RAW, which are calc records used to combine the error from $(STREAM_PV) with the value intended for the PV $(PV_NAME).

Important: When using an error setter, do not set the PV value directly. In the example given above, READING is to have the same error as UNITS. When other PVs need to change the value of READING they must instead write to READING:RAW.A. This is the intermediate PV created by the error setter.

Similarly, writes to the PV SP should instead by written to SP:RAW.A to allow the error setter to work so that the error is shared with UNITS.

If you need to use the error setter for PVs that are defined in a .db file instead of .template file, the .substitutions file for that .db file needs to have a different name than the .db file, otherwise the error setter will not work.

Calibration Range

Calculates the maximum and minimum values of a selected calibration file. You can load this db with macros using

dbLoadRecords("$(UTILITIES)/db/calibration_range.db","P=$(P),BDIR=TEMP.BDIR,TDIR=TEMP.TDIR,SPEC=TEMP.SPEC,HIGH_PV=TEMP:RANGE:OVER.B,LOW_PV=TEMP:RANGE:UNDER.B")

Where TEMP is a cvt record which uses the calibration file. The max value is outputted to HIGH_PV and the minimum to LOW_PV.

Shell Utilities

There are some IOC shell utilities defined in C:\Instrument\Apps\EPICS\support\utilities which can be used in an IOC shell to help startup IOCs. The doxygen docs are here http://epics.isis.rl.ac.uk/doxygen/main/support/utilities/.

calc

Performs an arithmetic operation on an expression and return the integer value to a specific environment variable:

calc("ENV1","1+1",1,2)

The arguments are as follows:

1. The output environment variable
2. The expression to be evaluated
3. Options
4. The output length

My best guess is that the expression is evaluated using the calcPerform method from the EPICS standard library so the expression should match the syntax as used in a calc record.

The options are detailed in ioccalc.cpp in the utilities directory.

Examples can be seen in the Galil and McLennan motor records.

dcalc

As calc, but returns a double value. The 4th argument is for the number of decimal places, not the value length.

dcalc("ENV1","0.1*0.2",1,2)

An example can be seen in the Eurotherm IOC, file st-timing.cmd.

stringtest

TODO

stringiftest(resultvar, lhs, operation, rhs)

Defines an environment variables as empty or a comment depending on if lhs is empty. The variables defined are:

• IF<resultsvar> '#' if empty; otherwise ' '
• IFNOT<resultsvar> ' ' if empty; otherwise '#'

parameters

1. resultvar - the basename of the environment variable to set
2. lhs - the string to test
3. operation - set the first bit for verbose mode
4. rhs - does nothing

The operation argument is given as a decimal representation of binary flags:

Operation	Flag
Verbose	0x1
length > 0	0x2
lhs == rhs	0x4
Inverse output	0x8

To get the operation that you require, add the flag value in decimal. For example, to check if a string has finite length, your operation would be 2. However, if you would like your flag to check if a string has a zero length, then add the inverse flag value 8, meaning your operation would be 10 (8+2). To add a log for this operation, add the verbose flag of value 1, so the total value is 11.

For debugging purposes it is advisable to add the verbose/logging flag of value 1 to your operation.

Example

From the DKFPS IOC:

stringiftest("POLAR" "$(POLARITY="BIPOLAR")" 5 "BIPOLAR")

The operation value is 5, or 4+1, so this checks the lhs ($(POLARITY), which defaults to "BIPOLAR") equals the right hand side "BIPOLAR", and puts the result in the $(POLAR).

setIOCName

TODO

getIOCName

TODO

getIOCGroup

TODO

mkdir

TODO