Electrical Interfaces
AGD155 Product Manual Rev.2.2
Page 30
3.4.9 Interfaces X11, X12: CAN Bus, RS232 and RS485
Figure 18: Serial Communication Connectors
Connector X11 and X12: CAN, RS232, RS485
Pin #
Name
Description
1
GND
Digital Ground
2
RS232_RX
RS232 input (receive at product)
3
RS232_TX
RS232 output (transmit from product)
4
RS485_B
RS485 bus, inverted
5
RS485_A
RS485 bus, not inverted
6
Sync
Reserved for future use
7
CAN_L
CAN bus, Low
8
CAN_H
CAN bus, High
Connector type
RJ45 LAN 10/100Base-T connector
Mating connector part number Any CAT5e compatible shielded connector
Cable
CAT5e or higher, standard Ethernet straight cable
Wiring
26 AWG, insulation rated for 100 V
Dual port connector
The serial port is a dual-port RJ45 connector. The two ports have identical pinouts and
are interchangeable. Two ports are provided to support daisy chain connection of a CAN
bus or RS485. It can be also used to connect two types of communication channels at the
same time, instead of splitting a cable from a single RJ45 connector.
CAN bus and RS485 terminators
The CAN bus lines have an optional 120
Ω
terminator that is connected/disconnected by
DIP switch #1 in the DIP SW interface (on the top panel). Setting dip switch #1 to the ON
position connects a 120
Ω
terminator between CAN_H and CAN_L. The terminator is
required only in the last unit in the CAN bus chain.
The RS485 lines have a built-in (not optional) 120
Ω
terminator. Communication
performance may be degraded if too many units are placed on the RS485 chain.
