Pelco C1977M-D manual Connecting Data Terminals, Control Terminal Port

Connecting Data Terminals

The unit has two serial interfaces—one at the back and another at the front. They serve different purposes and cannot be used interchangeably, as explained in the following.

Control Terminal Port

For local control and configuration of the unit, you can connect a data terminal (for example, a PC running a standard terminal program) to the serial interface labeled Control Terminal on the rear panel. The 9-pin DSUB connector features a standard RS-232 interface that can be connected to a PC’s COM port.

You can use a standard terminal program to communicate with the unit. The default parameters are set to 19200 baud with 8 bits of data, 1 stop bit and no parity bit (8N1).

To access the online help, type ? (a question mark) in the terminal window. For more information on the command set, see the Configuration section. This mode allows the control port to be used to send serial data that requires flow control.

You can configure the RS-485 halfduplex mode in the web browser. The RTS and CTS signals are enabled for flow control.

If this RS-485 mode is chosen, the camera control data is transferred automatically to the Control Terminal port. Certain cameras with fixed data length require the buffered RS-485 mode. (This halfduplex mode is not required for interfacing to any Pelco product.)

					Pin	Name	Direction	Description
VIEWED FROM SOLDERING
					1	DCD	Input	Data Carrier Detect
SIDE OF PLUG
1	2	3	4	5	2	RXD	Input	Receive Data
					3	TXD	Output	Transmit Data
					4	DTR	Output	Data Terminal Ready
					5	GND		Ground
6	7	8		9	6	DSR	Input	Data Set Ready
					7	RTS	Output	Ready To Send
					8	CTS	Input	Clear To Send
					9	-	-	-

Figure 20. Control Terminal Port Pin Assignments in RS-232 Mode

[ 24 ] Pelco Manual C1977M-D (6/02)