4. Cascade Connect Configuration
Preliminary Notes
In the previous section above, we defined the names of two Cascade Connect configuration files that will need to be used by the two Cascade Connect programs. We now have to define these two configuration files, called indir1.ini and indir2.ini. These configuration files tell one Cascade Connect to link to datahub a and the other Cascade Connect to link to datahub b.
Use the Cascade Connect Setup program to create these new configuration files.
Step-by-Step Procedure
The configuration file for datahub a:
The Program to Launch field should be empty (Do not enter any data in this field).
The Program Arguments field should also be empty.
In the QNX/UNIX Hosts field, type the name of the QNX computer that is running datahub a.
In the TCP Service field, type cascade.
In the Cascade DataHub Domains list, type default and a (the names of two datahub domains), as shown below:
In the Default Domain field, select default. This is because we need the Cascade DataHub to transmit data points with the domain name prefix (e.g. a@input34). If we define only one domain and call it the default domain, then the Cascade DataHub will not send data to Cascade Connect using the a@ prefix in each message. If a Cascade Connect program registers with the Cascade DataHub and informs the datahub that it considers the datahub to be the default domain, then the Cascade DataHub will not attach a domain prefix to the messages it sends to that particular Cascade Connect link.
You need to force the Cascade DataHub to attach the a@; prefix to all points that it sends to the InTouch application. You do this by telling the Cascade DataHub that the default domain name is called something else or may not even exist, (we have chosen the name default). This will tell the datahub that it is not the default datahub for this Cascade Connect client and so it will attach the domain prefix to each point that it transmits to InTouch.
In the Domain Separator field, type @.
In the Cascade DDE Service field, type cascade1.
In the Cascade DDE Topic field, type data.
In the Client Service field, type VIEW.
In the Client Topic field, type TAGNAME.
Save the file as indir1.ini.
The configuration file for datahub b:
The Program to Launch field should be empty (Do not enter any data in this field).
The Program Arguments field should also be empty.
In the QNX/UNIX Hosts field, type the name of the QNX computer that is running datahub b.
In the TCP Service field, type cascade.
In the Cascade Domains list, type default and b (the names of two datahub domains), as shown below:
In the Default Domain field, select default.
In the Domain Separator field, type @.
In the Cascade DDE Service field, type cascade2.
In the Cascade DDE Topic field, type data.
In the Client Service field, type VIEW.
In the Client Topic field, type TAGNAME.
Save the file as indir2.ini.