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Serial
Port
Configuration
Menu 2: Serial Port Configuration
Handshaking
Select handshaking:
1 For None
2 For Software Handshaking
3 For Hardware Handshaking
Enter Request :
Select 1), from the Serial Port Configuration Menu
for the
Handshaking menu,
Default is None
Select 2), from the Network Configuration Menu
configures Handshaking, Baud Rate, Word Size,
Stop Bits, and Parity through either the serial or Ethernet ports using the menus. RTS and DTR Line
Drivers can only be configured through the phone line via a modem. The
default settings
are
9600bps, 8 data bits, no parity, one stop bit, RTS and DTR High
.
IMPORTANT:
Communications with the terminal computer connected to the port will be lost
until the serial port configuration of the terminal computer matches the unit’s serial port.
+----+------+-----------------+------+------+------+------+---------+----+----+
|Port|Device| Device | Baud | Word | Stop |Parity|Handshake|LineDrive|
| | Type | Name | Rate | Size | Bits | | |DTR |RTS |
+----+------+-----------------+------+------+------+------+---------+----+----+
| 1 | RS232| EIA-RS232 | 9600 | 8 | 1 | None | None | HI | HI |
+----+------+-----------------+------+------+------+------+---------+----+----+
Handshaking......................1
Baud Rate........................2
Word Size........................3
Stop Bits........................4
Parity...........................5
RTS Line Driver Inactive State...6
DTR Line Driver Inactive State...7
Modem DCD Connection Mode....8
DS62-MD4 Module ONLY
Enter Request :1
For a simple communication between modems three connected lines are needed: TX, Rx, and Ground.
For the data to be transmitted, both sides have to be clocking the data at the same baud rate. While this
method is sufficient for most applications, it is limited in being able to respond to problems such as the
receiver getting overloaded. This is where serial handshaking can help.
Software Handshaking:
This style uses actual data bytes as control characters. The lines necessary
are TX, Rx, and ground since the control characters are sent over the transmission line like regular
data. The two control characters, XON and XOFF are characters sent by the receiver of the data to halt
the transmitter during communication.
NOTE:
A drawback to this method is also the most important fact to keep in mind. In ASCII
transmissions these character values are non-character values; however, data being transmitted via
binary, it is very likely that these values could be transmitted as data and the transmission would
fail.
