Porovnávané verzie

Kľúč

  • Tento riadok sa pridal
  • Riadok je odstránený.
  • Formátovanie sa zmenilo.

DDE Client communication protocol

Supported device types and versions
Communication line configuration
Communication station configuration
I/O tag configuration
Literature
Changes and modifications
Document revisions

Kotva
typy_verzie
typy_verzie
Supported device types and versions

...

Communication supports the DDE Client access using the XlTable data format (the format used by e.g. MS Excel, Wonderware Intouch I/O Servers) or CF_TEXT data format.

Kotva
komunikacna_linka
komunikacna_linka
Communication line configuration

...

Communication with the DDE Server requires a separate line. There is not possible accessing Accessing several servers from one communication line is not possible.

  • Communication line category: DDE.
  • Line parameters (the DDE - parameters tab):
  • Server - DDE server name (e.g. MS Excel „Excel“).
  • Impersonate user - if the option is checked, the communication line will connect the NetDDE with the following name and password to the NetDDE.
  • Name - system user name.
  • Password - system user password.

Note: You can impersonate just an user with the logon rights  The user you want to impersonate must have Log on as a batch JobJob system privileges.

Kotva
komunikacna_stanica
komunikacna_stanica
Communication station configuration

...

  • Communication protocol: DDE Client.
  • Station The station address is the DDE Topic name (a string containing up to 50 characters).


Station protocol parameters

Table 1

KeywordFull nameMeaningUnitDefault value
Kotva
req
req
REQ
RequestIf the value is Yes, after each writing a value,
there will be sent the
a request for
backward
the reading of the value will be sent.YES/NONO
Kotva
type
type
TYPE
Server TypeType of the DDE server for communication:


  • WARM -
supporting 
  • supporting XTYP_ADVSTART transactions,
  • COLD - periodic reading the values using the XTYP_REQUEST transaction.
COLD/WARMWARM
Kotva
format
format
FORMAT
Data Format
Used data
The Data clipboard format to be used for data transmission.XLTABLE/TEXTXLTABLE
Kotva
time
time
TIMEOUT
Transaction Timeout
Timeout
A timeout of the function DdeClientTransaction, which determines the maximum amount of time (in
miliseconds
milliseconds), that the DDE client will wait for a response from the DDE server in
a
the synchronous transaction.ms1000

Kotva
merany_bod
merany_bod
I/O tag configuration

...

Possible types: Ai, Ao, Ci, Co, Di, Do, TxtI, TxtO.

Address The address is the DDE Cell name (a string containing up to 50 characters).

Note: If the initialization of the connection to the server, topic, or cell has failed, the attempt to connect is repeated in the interval of 5 seconds. It The same is true also when the connection is lost (server shutdown etc.).


Connection to the server via NetDDE

If the DDE server is installed on other PC within a local computer network, you can establish a connection via the NetDDE interface. For such a connection is validthe following rules apply:

  • DDE server name (in the line configuration) is defined in the form of \\computer_name\server, where computer_name is the network name of the PC with running DDE server (e.g. \\WRK_PC\Excel).
  • On the PC with running DDE server, there must be run the Network DDE service must be running. You can run it as followsalso manually: Start menu -> Settings -> Control Panel -> Services, find Network DDE” DDE and click Start. In case of the you need an automatic start-up Startup… and switch , change the Startup type to Automatic -> OK.
  • On the PC with a process D2000 KOM process as a DDE Client, the Network DDE service is run automatically at occurrence of the first request for the NetDDE server. If you are experiencing a problem with access rights, there will be displayed the Logon dialog box for entering access name and password, which are valid on the PC with the DDE server, will be displayed. Usually, it is necessary to use the Win NT system utility "ddeshare" on the PC with the DDE server for configuration of access right of individual users to individual DDE servers, topics, and cells.


Example of communication testing

It is possible using the MS Excel program. Run the MS Excel as the DDE server using the switch /e e.g. from the command prompt - excel.exe /e.

Complete access to a DDE cell is as followsin the following format:

Excel|Sheet1!”R1C1”

Where:

  • Excel is the server name. Configure a line of DDE category and enter the DDE server name to Excel.
  • Sheet1 is a topic name. Configure the station with protocol station = "DDE Client XlTable and " and enter the DDE topic name Sheet1. Other tab sheets have similar names are similar in the form of Sheetx if they were not called differentlyform Sheetx unless those sheets have been renamed.
  • R1C1 is the name of a DDE cell. Configure an I/O tag and enter the DDE cell name R1C1. The name means Row 1, Column 1 and the form of the . The other cells have similar names is RxCy.in the form RxCy (e.g. R2C12).

This The naming is valid only for English versions of MS Excel.

Kotva
literatura
literatura
Literature

...

-

Kotva
zmeny_upravy
zmeny_upravy
Changes and modifications

...

  • May 20th, 2002 - added TEXT data format + COLD/WARM link.

Kotva
revizie
revizie
Document revisions

...

  • Ver. 1.1 – February 8th, 2000 – document update
Info
titleRelated pages:

Communication protocols

...