Siemens 7XV5450-0BA00/BB, Manual

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i
NOTE
The RS232 interface is disabled in the receive direction (RX) and in the transmit direction (TX) in compatibi-
lity mode.
For more information, see 3.5 Ring Topology .
External Master Redundancy in a Star Topology
Mode Data Transfer
External master redundancy in a
star topology
Master 1 = RS232 Receive Channels Transmit Channels
RX RS232 (receive)
R2
R1, R3 to R5 → T1 to T5
→ TX RS232 (transmit), T1, T3 to T5
→ TX RS232 (transmit), T2
Master 2 = fiber-optic channel 2
Extended mode FO1: R1 and T1 are additional slave channels
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NOTE
Only one master can be active at any time, that is, either RX RS232 or R2! Protocols communicate which
master is active, and which master is in standby mode.
The active master transmits data, the master in standby mode only “listens” to the bus. The collision mecha-
nism may be a method for determining the active/standby master.
For more information, see 3.4 Star Topology with Master Redundancy (Extended Mode) , Figure 3-2 .
External Master Redundancy in a Star Topology
Mode Data Transfer
External master redundancy in a
star topology
Master 1 = fiber-optic channel 1 Receive Channels Transmit Channels
R1
R2
RX RS232 (receive), R3 to R5 → TX RS232 (transmit), T2 to T5
→ TX RS232 (transmit), T1, T3 to T5
→ T1, T2
Master 2 = fiber-optic channel 2
Extended mode
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i
NOTE
The RS232 interface is an additional slave when the RS232 cable has been inserted and pin 7 and pin 8 on
the DIGSI cable have been shorted. Otherwise, the RS232 interface is disabled.
Only R1 or R2 can be active at any time. Protocols communicate which master is active, and which master is
in standby mode.
The active master transmits data, the master in standby mode only “listens” to the bus. The collision mecha-
nism may be a method for determining the active/standby master.
For more information, see 3.4 Star Topology with Master Redundancy (Extended Mode) , Figure 3-4 .
Application Examples
3.2 Operating Modes and Data Transfer
24 Accessories, Mini Star Coupler, Manual
C53000-G9050-C595-1, Edition 05.2020