You will need to establish a network DDE
(NetDDE) connection between the client and server applications.
There are numerous KB articles about this, but in summary ensure:
- Netdde.exe is running on both PCs;
NT: will be running by default on NT.
Win95: Suggest adding it to Startup folder. It resides in the
Windows directory.
- You can browse the Server PC from the Citect PC;
Eg from the START | RUN menu type \\<Server_pc_name>\C Where
C drive has been shared on the remote.
The <Server_pc_name> can be found via the Control Panel |
Networks | Identification Tab on the remote.
- You have established a share on the DDE Server (Excel)
PC;
NT: has a built in share manager. Type "DDE Share" from the START |
HELP menu to get a hotlink to it.
Win95: You will need to install DDESHR.EXE or another share manager
application to create and manage your shares.
(see our FTP site for a copy)
For this example the share details are as follows: (Refer to KB
Q1927 for an explanation of Wildcard sharename syntax)
Share Name: My_Excel|* <the share name is completely
arbitrary, but |* is essential>
Application Name: Excel <must be the registered name of the
DDEServer application>
Topic Name: * <as per Wildcard convention>
Item Name: <can leave blank>
Level 1 Access Authority: (note you MUST have the following checked
in order for communications to work correctly)
Request <checked>
Advise <checked>
Poke <checked>
- Citect Configuration:
|
Boards form
|
|
| Board
name: |
Board1 |
| Board
type |
leave
this field blank
|
| Address: |
0 |
|
Ports form
|
|
| Port
name: |
Port1_Board1 |
| Port
number: |
1 |
| Board
name: |
Board1 |
|
I/O Devices form
|
|
| Name: |
Net_DDE_Dev |
| Number: |
1 |
| Address: |
\\<Server_pc_name\My_Excel|Citect.xls
<This follows the Application|Topic convention where the
Application is the remote PC and share name and the Topic is an
existing spreadsheet you are connecting to.> |
| Protocol |
DDEDRV |
| Port
name: |
Port1_Board1 |
|
Variable Tags form
|
|
| Name: |
Tag_1 |
| Data
Type: |
INT |
| I/O Device
Name |
Net_DDE_Dev |
| Address: |
R1C1 |
Place the tag on a page, configure a hardware alarm page,
compile and run the project.
- Go to the page and confirm that communications have been
established. If not, check for hardware alarms, and recheck each
step above.
Notes and Tips:
A useful DDE Conversation checking tool is DDESpy which is
shipped with Visual Basic I believe.
If establishing numerous conversations to a number of
spreadsheets, configure a new Citect I/O Device for each, but only
configure a single Port and Board.
Refer to online help for fine tuning the DDEDrv communications.
eg tweaking the Watchtime, Timeout, Delay, Max Pending
parameters.
Citect must be able to establish an Advise loop with the server
application as well as being able to make requests of the server
application. You may also want Citect to be able to poke data to
the DDE server. The Share must be configured to grant the authority
for all of the above transactions.
Use [DDEDRV]<devicename>.AdvInitData parameter to control
how variables in an advise loop get initialised. See KB articles
Q1848 and Q1849
for details. |
