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Carlson RT4 User Manual
Congure pin 9 as input or power supply: Pin 9 is the Ring-In signal
input. It is rarely used by devices anymore and has become a popular
pin to provide a power source to an RS-232 device.
Select Input if your device uses Ring-In signal or if it does not need to
be powered from the RS-232 port.
Select Power supply enabled to make pin 9 a power supply to be used
by the RS-232 device. The power supply is enabled automacally
without needing any interacon with the COM port. Depending on the
model, the power supply supplies either 5 VDC or 12 VDC.
• Select DTR enables power supply to make pin 9 a power supply (5 VDC
or 12 VDC depending on model). The power supply remains o unl
the user applicaon opens the COM port and asserts the DTR signal.
When the DTR signal de-asserts, the power supply turns o again.
• Check Disable power supply during sleep to cause the power supply to
automacally turn o when the tablet is in sleep mode. This can allow
the RS-232 device to conserve baery power in sleep mode. If your
app and/or RS-232 device experiences communicaon failures when
the RT4 enters or exits sleep mode, then leave this opon unchecked.
Oce Docking Staon
The Oce Docking Staon enables you to perform the following funcons:
• Charge your RT4 Rugged Tablet
• Use your RT4 as a desktop computer
• Transfer data to or from another computer or network via the
Ethernet connecon
Oce Docking
Staon