Chapter 9. Serial Interface Operation; Overview - Comtech EF Data CDM-710 Installation And Operation Manual

Chapter 9. SERIAL INTERFACE
OPERATION

9.1 Overview

The serial interface is an electrical interface. It is either an EIA-232 connection to control one remote device, or an
EIA-485 multi-drop bus to control multiple remote devices. The interface transmits data as ASCII characters in
asynchronous serial form. This control or status data occurs in packets of variable length.
9.1.1 EIA-232
In this configuration, the Controller device is connected directly to the Target. This connection is a two-wire plus
ground connection. Controller-to-Target data is carried on one conductor using EIA-232 electrical levels. Target-to-
Controller data is carried in the other direction on the other conductor.
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