Serial Port Pin 9; Enable Handshaking - Honeywell VX3Plus Reference Manual

Serial Port Pin 9

To configure the COM port to supply power to an external scanner tethered to the COM port, check the checkbox for Power on
Pin 9 (+5V). The external scanner is powered by the VX3Plus's power source. Wireless external scanners use their own power
source.
To configure a COM port for Ring Indicator (RI) on Pin 9, uncheck the checkbox for Power on Pin 9 (+5V) (disabled).
The default is Off (RI enabled) for all COM ports.

Enable Handshaking

To enable handshaking on the indicated serial port, check the Enable handshaking box.
The default is disabled (unchecked)
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