Sockets - page of object PmRoot
Global configuration of the communication by sockets Definition of socket groups within them the communication will proceed. The groups are divided into SERVERS
Communication defined on this page is considered obsolete
and it is better to use commnication based on the PmComm
object - for example by the PmChar
driver for Ethernet.
| Sockets enabled||If checked, then the socket communication in the application is enabled.|
|System port||Number of the system port necessary for the system sockets initialization. Numbers less than 1024 are reserved for registered applications, that's why this number should be in the range from 1024 to 65535. It isn't ensured that, for example, the port number 3277 (preset value) won't be occupied by another running application that are not registered but it is using network communication.|
|Network type||Definition of the network, through which it is communicated.|
Microsoft TCP/IP - net with the TCP/IP protocol
NOVEL SPX/IPX - Net with the SPX/IPX protocol. This option is obsolete and it is not used.
|Error recovery socket timeout [s]||Time in seconds after which the communication is re-enabled and at the same time the communication over the client group is called if a critical error occurred during the last data transfer. Recommended values are in seconds.|
In the Client/Server groups window the names of groups are displayed that can be edited by the buttons on the right. By the New or Edit button the Socket client group/Socket server group window is opened where it is possible to add a new or to edit the selected group. By the Delete button it is possible to remove the selected group.
It is possible to communicate within more PROMOTIC applications on one or more PC. But it is necessary to have only one application that contains server groups started on one PC. If more server applications have to be started on one PC, then each of these applications must use different serial port number
. The number of applications containing only client groups on one PC is theoretically unlimited. The whole number of all socket groups should practically be in tens at the most.
Each group communicates on its own port
. If the group has not defined this port explicitly by the designer, then this port can be get by the system socket - see the configurator "System port". It means that the group sends a request for the port number of the group to the server by means of the system socket. The server responds with the assigned number to the group and then the group communicates only to the port with this assigned number.