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Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

setting/using variables within a QSF

I'd like to be able to set text (and potentially numerical values) to variables that can be recalled throughout the QSF. QSF files are supposed to be interpretted as TCL files, but they don't support all TCL commands.

I've already tried the example below, but this is basically what I want to do:

# declare and initialize the variable:

set VAR_NAME VAR_VALUE

.

.

.

# use it in a constraint later in the QSF file:

set_instance_assignment -name MISC_CONSTRAINT ON -to $VAR_VALUE

This is easily done in SDC files with TimeQuest, but it doesn't seem to work in a QSF. Anyone do this successfully? Any ideas?

I didn't see anything relevant in the QSF manual that supposedly lists all of the recognized commands/constraints, but I know there are supported commands that aren't in there (such as "source"), so I can't rule it out. That begs another question; is there a document that defines what TCL commands are successfully interpreted within a QSF?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    10 years ago

    I have not been able to use the tcl syntax you mention in the qsf, but a possible workaround is to put your qsf assignments in a tcl file where you can use more of the standard syntax of tcl. Then add the following global assignment in the qsf

    set_global_assignment -name SOURCE_TCL_SCRIPT_FILE <filename_here>.tcl

    Then in the file <filename_here>.tcl add the lines...

    set VAR_NAME VAR_VALUE

    set_instance_assignment -name MISC_CONSTRAINT ON -to $VAR_NAME

    I, admittedly have never used set_instance_assignment in this separate tcl file, but I have used set_parameter -name PARAM_NAME $VAR_NAME and that worked.