Typical Application; Serial Port Pinout - Quest Engineering Q232-STS User Manual

Q232-STS
RS-232 Serial Transfer Switch

Typical Application

RS-232
Radio
Galvanic Isolation
The Q232-STS provides 2,000 Vrms isolation
between the following circuits:
• Battery Input
• Controller Interface
• Primary and Backup Links
095-160140-1000, Rev. A00
Battery
Interlocking
Modem
Controller
© QuEST Rail LLC 2018

Serial Port Pinout

Primary Port
Signal Pin (DB9 M)
TXD 3
RXD 2
RTS 7
DCD 1
COM 5
Backup Port
Signal Pin (DB9 M)
TXD 3
RXD 2
RTS 7
DCD 1
COM 5
Controller Port
Signal Pin (DB9 F)
TXD 3
RXD 2
RTS 7
CTS 8 (Internally connected to RTS)
DCD 1
COM 5
Operation
When the Backup Port DCD signal is de-
asserted, all communication signals are routed
between the Primary Port and Controller Port.
When the Backup Port DCD signal is asserted
and data is received on the Backup Port, all
communication signals are routed between the
Backup Port and Controller Port.
LEDs provide status for input power, RS-232
signals, and active link.
User Manual
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