Black Box RS0232, RS-422 manual LEDs

RS-232↔RS-422 INTERFACE CONVERTER

THE RECEIVER TERMINATION SWITCH

This switch is marked S1 on the printed circuit-board diagram in Figures 3-1 and 3-2. This switch serves to terminate the receiver with pull-up and pull-down resistors in order to designate the receiver state and enable the Converter’s anti-streaming function. Setting the switch to the ON position closes the switch, setting the switch to OFF opens the switch.

3.2 LEDs

The RS-232↔RS-422 Interface Converter is equipped with seven LEDs located on the front panel that indicate the status of INPUT signals.

The three LEDs on the right side of the front panel show conditions on the RS-232 interface: DSR (Data Set Ready), CTS (Clear To Send), and Data.

The three LEDs on the left side of the panel show the same conditions on the RS-422 interface: DSR (Data Set Ready), CTS (Clear To Send), and Data.

The LED labeled PWR, located in the center of the front panel, indicates when power is applied to the unit.

Figures 3-5 and 3-6 illustrate signal flow in both the DTE and DCE configurations.

NOTE

Some LEDs may be lit when no input signal is present. This is not a malfunction, but a floating state condition at the input that causes the output of that driver to indicate a positive voltage condition.

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