Experimental Physics and
Industrial Control System

"Kenneth Evans, Jr." <[email protected]> · Wed, 11 Feb 2004 14:46:12 -0600

GDCT has been modified so GDCT files can be converted to VDCT files.
For more information see the GDCT documentation page:
http://www.aps.anl.gov/asd/controls/epics/EpicsDocumentation/ExtensionsManua
ls/GDCT/GDCT313.html
(You may have to paste this link in two parts if it gets separated by
a linefeed.)

In summary:

There is an option on the file menu to save the working database as a
vdb file for use in VDCT. The saved file must have a .vdb
extension. Although the conversion is not perfect, your basic
arrangement should be preserved, making it much easier to start
working in VDCT than when starting from scratch.

Connecting lines will follow VDCT's location algorithms and will not
typically be in the same place as in GDCT. You can arrange them in
VDCT as you like.

All prompt fields (those modifiable in a graphical database) are
specified in the vdb file, but with the visibility set to "never
shown". By double clicking the record to bring up the Inspector in
VDCT, you can easily change whether they are shown or not.

VDCT shows all records, whereas GDCT shows only the ones specified
(listed in the db file as grecord instead of record). All of the ones
that are not shown in GDCT are placed in the lower right corner of the
VDCT page, and you will have to place them elsewhere yourself.

External Links are shown as Text.

When using VDCT, you may encounter problems owing to bugs in VDCT. The
following appear in version VDCT 2.4 but may be fixed in later
versions.

VDCT will tell you that the DTYP field must be defined before any
DBF_INPUT/DBF_OUTPUT fields. This is typically owing to TSEL appearing
before DTYP when the database is written in the standard way using
dbWriteRecord(). The warning is wrong and may be ignored. DTYP only
needs to be defined before the two fields INP and OUT.

VDCT incorrectly converts DISV="1" and UDF="1" (the defaults for these
fields) to DISV="" and UDF="" when it saves the converted file after
you have edited it. When read in the server "" is interpreted as "0",
the opposite of the default value for these fields. For DISV this is
an especial problem as it can cause the record to be disabled, usually
not what you want. The only way to fix this problem seems to be to
eliminate all lines containing DISV and UDF in the vdb file, including
those in the graphical specification section at the bottom. Then the
default values will be used. It is not sufficient to correct or
eliminate DISV and UDF fields in the database part. VDCT will put them
in incorrectly again the next time.

VDCT gives a warning that Value '' is not valid for menu 'menuYesNo ->
template definition?... This does not happen when reading the
converted file, but does happen when reading files that VDCT saves
itself. It seems to be benign.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System