Moxa Technologies CP-132U Series RS-485 Programming, ADDC Automatic Data Direction Control

Software Installation

RS-485 Programming

If you intend to use your CP-132UL Series board for RS-485 applications, you can refer to the RS-485 programming guide below, and also see the chapter, “Connection Cables and Cable Wiring,” for more details about RS-485 operation.

The CP-132UL Series supports only 2-wire half-duplex RS-485 communication. In this case, the data+/- pins are used for both data transmitting and receiving, depending on the mode selected. The modes available are ADDC™ (Automatic Data Direction Control), or By RTS.

ADDC™ (Automatic Data Direction Control)

The ADDC™ scheme is the best solution for RS-485 applications. To use ADDC™ mode, set the mode switch to the ON position.

Under this mode, no extra code is required to control data transfer (both data transmitting

CP-132U Series User’s Manual 4-5