Node Types
A node type defines an interface of server communication with a device (a communication protocol is defined in the plugin). In Multi-Protocol MasterOPC Server, the following node types are provided:
COM – serial interface (MASTER or SLAVE)
TCP/IP – TCP/IP network (MASTER or SLAVE)
PROGRAM – program interface (developed by a user). A node of that type only executes a user script.
If this node type is used, extra sections are added to the dialog of node parameters .
In the COM Settings section, parameters of a COM port are set:
Port – number of a COM port; the default value is 1 (COM1)
Rate – an exchange rate (1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600 or 115200 bauds); the default value is 9600
Data – number of information bits (5, 6, 7 or 8); the default value is 8
Parity check – parity check (No, Odd, Even, Mark, Space); the default value is No
Stop bits – number of stop bits (1, 1.5, 2); the default value is 1
Inter-character timeout (ms) – a maximal admissible interval between sends of bytes. Exceeding of that value is diagnosed as an error. The default value is 0 (0 corresponds to 50 ms).
Echo – this mode is used for respective converters, which support the echo mode (converters VSCOM, Mercury 221). In this mode, each sent byte of a converter returns back to the receive buffer right away.
Modem – a value of this parameter must be TRUE if a modem (or GSM modem) is connected to the COM port. Otherwise, a value of this parameter must be FALSE. If Modem=TRUE, the Modem Settings section is available, and the Own telephone setting is available in settings of devices of that node (see The Dialog of Device Parameters ).
In the Modem Settings section, parameters of a modem (GSM modem) connected to the COM port are set:
Phone number – phone number (in the international format)
Initialization string – an AT command of initialization according to the modem documentation. Example:
ATE0Q0V1X4&C0&D2&S1S0=0S7=60+CBST=71,0,1)
Connection timeout (s) – maximal time to wait for connection with a device; the default value is 60
Hold the connection – if TRUE, the Connection hold timeout (s) parameter is available :
Connection hold timeout (s) – if there is no exchange over the bus during the time defined by this parameter, GSM connection is terminated (the connection is held during the timeout).
Connection – interface (rs232 or rs485)
In the Additional Settings section, the following parameters are set:
Forced disconnection in each cycle – TRUE/FALSE
If this node type is used, the TCP/IP Settings section is added to the dialog of node parameters .
In the TCP/IP Settings section, the following parameters are set:
IP address – IP address of the server; the default value is 127.0.0.1. (IP address can be set in a character format, e.g. "localhost" instead of 127.0.0.1) .
IP port – IP port of the server; the default value is 502.
Connection timeout (s) – this parameter is available only for TCP/IP Master. It defines a maximal time to wait for connection; the default value is 10.
Inter-character timeout (ms) – a maximal admissible interval between sends of bytes. Exceeding of that value is diagnosed as an error. The default value is 20.
If this node type is used, none of extra sections is added to the dialog of node parameters .