Axis Communications 250S - Manual (Page 46)

Unit Connections AXIS 250S User’s Manual 46
Appendix E - Unit Connections
The D-Sub Connector
The AXIS 250S provides one 9-pin D-sub connector, providing the physical interface for an
RS-232 port, used for connecting accessory equipment; such as stand-alone Pan/Tilt
devices for the remote positioning of connected video cameras.
A diagram of the RS-232 connector, complete with pin assignment table, is shown below.
The I/O Terminal Blocks
The two 4-pin I/O Terminal Blocks, A and B, are located on the rear panel and provide the
interface to: a single transistor output, four digital inputs, an RS-485 interface and GND.
This section describes the pinout, interface support and the control and monitoring
functions provided by the terminal blocks.
Note that the wiring for the pins on incoming plug connectors is not identical, but instead
on opposite sides in relation to each other. Check the rear panel before wiring.
Connector Pinout - Terminal Blocks A & B
Pin Function
1 CD
2 - RXD
3 - TXD
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
9 RI
Pin Function Description
A1 GND
A2 Digital Input 1 To activate, connect to GND.
A3 Digital Input 2 To activate, connect to GND.
A4 Digital output With a maximum load of 100mA and maximum voltage of 24V DC, this
output has an open-collector NPN transistor with the emitter connected
to pin 1. If it is to be used with an external relay, a diode must be con-
nected in parallel with the load for protection against any voltage tran-
sients.
B1 Digital Input 3 To activate, connect to GND
B2 Digital Input 4 To activate, connect to GND
B3 RS485A RS-485/422 - A (non-inverting). A half-duplex RS-485/422 interface for
controlling auxiliary equipment.
B4 RS485B RS-485/422 - B (inverting)
5 4 3 2 1
6 7 8 9