AMX AXlink Bus Controllers AXB-232++ - Manual (Page 7)

Installation and Wiring
3 AXB-232++ RS-232/422/485 Interface
Installation and Wiring
The AXB-232++ can be used as an independent RS-232/422/485-controlled interface by setting the
internal jumpers. Configure the communication parameters using the DIP switches on the front
panel.
Setting the Internal Jumpers
Setting jumper JP4 to terminate RS-422 input with 100 ohms
Terminating a device involves installing a 100 ohm line terminator, this is typically used to achieve
better communication and signal integrity. You will want to terminate when the communication is
at a high data rate or over a long distance. Termination can be harmful because it increases the
current in the line, and more radiation that could interfere with signals.
Jumper JP4 places 100 Ohms termination across RS422 receive data pins 5 & 6:
1. Disconnect the RS-232/422/485 connectors.
2. Unscrew the two screws on the rear panel, and remove the panel.
3. Slide the circuit board out of the enclosure.
4. Locate the JP4 jumper (FIG. 3).
5. Install the jumper in the 'ON' position (default setting = OFF).
6. Slide the circuit board back into the enclosure.
7. Replace the panel, and refasten the screws.
8. Reconnect the RS-232/422/485 connectors.
FIG. 3 Location of internal jumpers
CORP.
AXB-232++
1998
JP4
JP5
Internal jumper JP4
Internal jumper JP5
front