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Settings of the serial link parameters

Description:
Serial link communication parameters executed through the PmComm object can be defined in this configuration window. The window can be fired from the Base communication parameters configurator, if the communication protocol is assigned for serial link.
Serial link parameters setting:
Serial portSelection of the communication serial port.
Not set - The object is not connected to any port at the start of the application and the serial port can be selected dynamically by the algorithm (by the PmComm.OpenPort method).
Modem - The object is meant for the data transfer over the dialed phone line (over the PmModem object). The serial port is assigned by the PmModem.SetPmComm method or by the PmComm object configurator of the PmModem object.
COM1, COM2,..,COM66 - The specified serial port is opened at the start of the application. This port must be correctly configured and accessible in the OS Windows (no one can use it).

For serial link each PmComm object must have defined another communication port. For example, when one PmComm object communicates through COM1, then next PmComm object can communicate for example through COM2 (COM3,..) but it mustn't communicate through COM1.

Baud rateSelection of the baud rate (bps, bit per second).

This configurator sets the initial value of the property BaudRate.

Number of data bits Number of data bits selection. Appropriate value for the device, which it is communicated with, must be selected.

This configurator sets the initial value of the property ByteSize.

5
6
7
8
Parity Parity selection. Appropriate value for the device, which it is communicated with, must be selected.

This configurator sets the initial value of the property Parity.

NO
ODD
EVEN
Number of stop bits Number of stop bits selection Appropriate value for the device, which it is communicated with, must be selected.

This configurator sets the initial value of the property StopBits.

1 stopbit
1.5 stopbit
2 stopbit
Number of repeats after unsuccessful transmissionSelection of the number of repeating the message transmission if the response has been defective or it hasn't been received at all. This setting is meaningful only for the communication messages of the Master type. Preset value is 0 (i.e. without repeat).
Timeout between receiving 2 charsMaximum waiting time (in ms) between receiving two characters. After the expiration of the time the transmission of the message is terminated.

For many protocols it is not possible to specify in advance how many characters shell be really received. Then the receiving is terminated just after elapsing this timeout, which is not considered as an error but the detection of the end of the message. That's why it is not suitable to set the value of this timeout too high because this timeout is performed after every (even errorless) receiving the message.

Delay between receive-sendTime (in ms) that the object is waiting after receiving the message until next message is sent.
Filter ECHO charsSpecification if the received data have to be removed (filtered) because it goes about repeating characters transmitted from the message.

Note: Received filtered ECHO characters are recorded together with other characters in the INFO system in the /COMM/Monitor item.

No (default) - no filtr
Yes - filter. As many first received characters are removed as many characters were transmitted last. Must be set if the port (converter) returns transmitted characters.
RTS flow controlThe output signal RTS behavior and the usage of the input signal CTS. See PmComm.Rts.
log.0 - RTS is always set to 0, CTS is ignored.
log.1 - RTS is always set to 1, CTS is ignored.
handshake - RTS is used for handshaking, CTS is ignored. If an overflow of the input buffer threatens, the signal is set to 0, otherwise to 1.
log.1+CTS - RTS is always set to 1, CTS servers for the output flow control. The transmission is intercepted for the time when the signal is set to 0.
handshake+CTS - RTS is used for handshaking, CTS is used for the output flow control. The transmission is intercepted for the time when the signal is set to 0. If an overflow of the input buffer threatens, the signal is set to 0, otherwise to 1.
toggle - RTS serves for the control of the transfer direction. This is important in particular for the non-intelligent converters RS485 that require to control the direction of the transfer by the signal RTS. For details to the issue of the RTS signal control see Warning for RS485 serial interface.
DTR flow controlThe output signal DTR behavior and the usage of the input signal DSR. See PmComm.Dtr.
log.0 - DTR is always set to 0, DSR is ignored.
log.1 - DTR is always set to 1, DSR is ignored.
handshake - DTR is used for handshaking, DSR is ignored. If an overflow of the input buffer threatens, the signal is set to 0, otherwise to 1.
log.1+DSR - DTR is always set to 1, DSR servers for the output flow control. The transmission is intercepted for the time when the signal is set to 0.
handshake+DSR - DTR is used for handshaking, DSR is used for the output flow control. If an overflow of the input buffer threatens, the signal is set to 0, otherwise to 1. The transmission is intercepted for the time when the signal is set to 0.
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