Configuring serial ports

Configuring a serial port

To change the configuration of a serial port, using the Serial Manager:

If the serial port to be configured is on a remote computer, select Host Open host and choose the name of the remote computer.
Select View Ports to display the list of configured serial ports on your computer.
Select a port to configure.
NOTE: You cannot select a serial port which has a mouse or other pointing device attached.
Select Port Modify to modify the configuration of the selected port.
You can change the information for the following fields:

Port type
Select the type of port:

software flow control
Used with devices that require software flow control (XON/XOFF). This should not be used if binary data transfers are possible, for example with modems that provide data compression.
NOTE: The terminal port type is recommended for use with serial terminals and printers that use software flow control (XON/XOFF).
The device node used is /dev/term/nns.

hardware flow control
Used with devices such as serial printers that require bidirectional hardware flow control (RTS/CTS), or unidirectional hardware flow control (RTS/CTS or CTS/DTR).
NOTE: The modem port type is recommended for use with modems.
The device node used is /dev/term/nnh.

terminal
Used with terminals and serial printers which use a basic 3-wire serial connection (transmit data, receive data, and signal ground lines only) together with software flow control (XON/XOFF).
The device node used is /dev/term/nnt.

modem
Used with modems (including all high-speed modems, and modems that provide data compression).
The device node used is /dev/term/nnm.

NOTE: The use of software or hardware flow control may also need to be configured on the serial device and in the communications software to be used.
See ``Serial device node naming conventions'' for further information on types of serial ports and device node names.

Configure port
Select one of:

outgoing only
Used with serial printers and dial-out connections only.

incoming only
Used with serial terminals and dial-in connections only. This setting allows modems to answer (``auto-answer'') incoming calls but not to place outgoing calls.

incoming and outgoing
Used with both dial-out and dial-in connections. This setting allows modems to answer (``auto-answer'') incoming calls and to place outgoing calls.

NOTE: The ttymon(1M) port monitor is only enabled for the port when the port is configured to accept incoming connections.

Speed (bps)
Select the default speed for the serial port. The selected speed should not be greater than the capabilities of the UART chip that controls the port. Refer to ``UARTs'' for details of the limitations that different types of UART place on port speeds. Serial ports on most modern machines can operate at any of the standard speeds from 110 to 115200bps.
If auto is selected, the ttymon(1M) port monitor automatically detects and sets the serial port configuration. This setting is recommended for direct lines and serial terminals.
To set the number of data bits per character and type of parity, click on Port settings. The default values are 8 data bits and no parity.
You may change the information for the following fields:

Data bits
Select a value from the list: 7 or 8 data bits.

Parity
Select either even, odd or none.

NOTE: These values cannot be changed if the speed was selected as auto in the Speed (bps) field.
To set the trigger level of the UART, click on Receive buffer.
Adjust the slider bar to one of the values: 1, 4, 8, or 14. Select a lower value to alleviate data overruns (characters are being lost in incoming data). Select a higher value to improve performance by reducing the number of interrupts that the UART generates.
NOTE: The Serial Manager is unable to read the current trigger level of the UART. Consequently, a value of 8 is shown as default.
Click on OK to confirm the port's configuration.
Select Host Exit to leave the Serial Manager.