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Page 20 USER MANUAL ref 9011509-01 AFO485 and RFO485
3.6. Asynchronous Interfaces
On each RFO485, the asynchronous interface used can be different; for
example, the first modem can be connected to the PC using the RS232
interface while the second AFO485 can be connected to a PLC using the
RS485 or RS422 interface.
RS232 Interface
The RS232 interface is available on an RJ45 plug.
The CAB593 cable has a DB9 female connector for the RS232 link.
It must be ordered separately (see appendix 1).
The CD and DSR and CTS signals are closed by the RFO485 as soon as
it receives the modulation from both remote RFO485.
No control signal from the RS232 terminal (DTE) is necessary.
RS485 and RS422 interfaces
The unit has an RS422 interface (4 wires) and RS485 (2 wires) on the 6
point connector block.
These interfaces are not opto-isolated and must be used for short
distances.
The matching resistor of the bus is not included in the product.
The diagram of these interfaces is given in § 5.5.
3.7. Transmission failure output
3.7.1 Bus network
The transmission failure output is closed when a repeater detects the
modulation on the two optical links to which it is connected, even if no data
is received on either of the two lines.
The leds “lines 1 and 2” are lit.
The transmission failure contact is opened as soon as the modulation
is lost on one of the two optical links to which the repeater is connected or
if the repeater is powered off.
The corresponding led ( line 1 or 2) is extinguished.