Allen-Bradley SLC 500 Series User Manual

Publication 1747-RM001G-EN-P - November 2008
13-88 SLC Communication Channels
DF1 Radio Modem
When you configure the SLC 5/03, SLC 5/04, and SLC 5/05 processors for
DF1 Radio Modem, the following control line operation takes effect:
No Handshaking Selected - DTR is always active and RTS is always
inactive. Receptions and transmissions take place regardless of the states of
DSR, CTS, or DCD inputs. This selection should only be made when the
processor is directly connected to another DTE device.
Half-duplex with Continuous Carrier Selected- DTR is always active. RTS
is activated during transmission and during any programmed delays before or
after transmissions. Programmed delays include RTS Send delay and RTS Off
Delay. The DSR input signal must remain active for transmissions or
receptions to occur. The modem lost bit is set whenever DSR is inactive. The
DCD input signal is ignored.
Transmission requires CTS and DSR to be active. If CTS is inactive at the
onset of transmission, one second will be provided to wait for CTS to become
active before the message packet is discarded.
Half-duplex without Continuous Carrier Selected- DTR is always active.
RTS is activated during transmissions and during any programmed delays
before and after transmissions. Programmed delays include RTS Send Delay
and RTS Off Delay. The DSR input signal must remain active for
transmissions or receptions to occur. The modem lost bit is set whenever DSR
is inactive. The DCD input signal is monitored to determine if transmissions
are acceptable. If DCD is active, receptions are possible.
Transmission requires CTS and DSR to be active and DCD ti be inactive. IF
DCD is active at the onset of transmission, a configurable delay (DCD Wait
Delay) will wait for DCD to become inactive before discarding the packet. If
CTS is inactive at the onset of transmission, one second will be provided to
wait for CTS to become active before the message packet is discarded.
Modbus RTU Master
When you configure the SLC 5/03, SLC 5/04, and SLC 5/05 processors for
Modbus RTU Master, the following control line operation takes effect:
No Handshaking - DTR is always active and RTS is always inactive.
Receptions and transmissions take place regardless of the states of DSR, CTS,
or DCD inputs. This selection should only be made when the processor is
directly connected to another DTE device.

Allen-Bradley SLC 500 Series Specifications

General

Brand	Allen-Bradley
Model	SLC 500 Series
Category	Controller
Language	English