Capfast Compatibility

Compatibility mode
DBD mode
Comparison of Modes
    Property Sheets
    Schematic Files
    EPICS Database
    Link Fields
Configuration
Conversion from Compatibility Mode to Dbd Mode

Tdct supports two different modes of operation:

Compatibility Mode

By default, Tdct runs in "Compatibility" mode. In this mode
Note that in this mode there is a disconnect between the symbol files and edb.def which can lead to strange errors during database generation. Symbol files define which record fields can be changed interactively. edb.def defines which fields are written to the database. Default values on EPICS record symbols override the default values in edb.def.

Dbd Mode

In Dbd mode tdct fully parses the EPICS dbd files. In this mode

Comparison of Compatibility Mode and Dbd Mode

Property Sheets

Example of a property dialogue for a binary input record in Compatibilty mode:

property dialog for bi record in compatibility mode

Example of a property dialogue for a binary input record in Dbd mode:

property sheet for bi record in dbd mode

Schematic File

Analog input record on a tdct display and the corresponding section of the schematic file in Compatibility mode:

tdct display of ai record in compatibility mode

ai record in schematic file in compatibility mode

Analog input record on a tdct display and the corresponding section of the schematic file in Dbd mode:

tdct display of ai record in dbd mode

ai record in schematic file in dbd mode

EPICS Database

Comparison of the corresponding sections of EPICS databases in Compatibility mode (left) and Dbd mode (right):

database comparison

Link Fields

Links between EPICS records are established by specifying the target PV for an EPICS record link field.
If a record name, but no field name is given for the target PV, the VAL field is targeted.
In addition, the link properties for passive processing (NPP PP CP CPP CA) and severity transfer (NMS MS) can be specified for the link. Default is NPP NMS.

In Compatibility mode,  

links are specified by
  1. entering the link target PV name into the def(<link field>) property of the EPICS record symbol or 
  2. connecting symbol ports by wires
link properties are specified by
  1. adding the properties after the target PV (separated by white space) or
  2. using the pproc(<link field>) and palrm(<link field>) properties of the EPICS record symbol. If the link is specified with a wire, the link properties for passive processing and severity transfer can also be specified by double-clicking on the wire-segment which connects to the link field.
NOTE: in the EPICS record symbol set, which came with the Capfast distribution, there seem to be some inconsistencies. Not all links have the pproc and palrm properties, and on some records the properties do not get used properly when a database is built. We don't understand this fully and generally work around with 3).

In Dbd mode,

links are specified by
  1. entering the link target PV name into <link field> property of the EPICS record symbol or 
  2. connecting symbol ports by wires
link properties are specified by
  1. adding the properties after the target PV (separated by white space) or
  2. if the link is specified with a wire, enter the link properties into the <link field> property, preceded by ---, 
    e.g. --- PP NMS
    or double-click on the wire segment which connects to the link port to open a dialog for modifying the link properties.

Configuration

Capfast compatibility is controlled by a directive in the configuration file, which can have the following forms:

[option] dbdmode
[option] dbdmode false
[option] dbdmode true

If the directive is not present or present with the value false, tdct operates in Compatibility mode.
If the directive is present without value or present with the value true, tdct operates in Dbd mode.

Conversion from Compatibility Mode to Dbd Mode

Note: This Conversion is a one-way street. Once a schematic is converted to Dbd Mode, tdct cannot convert it back to Compatibility mode.

When tdct operates in Dbd mode and reads a schematic which was saved in Compatibility mode, the schematic is automatically converted to dbd mode. A warning message is issued to the user in order to avoid unintended conversion.

The conversion requires that two instances of EPICS record symbol libraries are defined in the tdct configuration file:
As Dbd mode obtains the default values for EPICS record fields from the dbd files, EPICS record symbols for dbd mode do not need to define any properties with the exception of the "type" property which is used to display the record type.

During the conversion of a schematic from Compatibility mode to Dbd mode handles record properties in the following way:
This assures that the functionality of EPICS databases does not change when tdct schematics are converted to Dbd mode.