B&B Electronics RS-485 manual Reading Digital I/O Command, AddrRD, States

Reading Digital I/O Command

The Read Digital I/O command returns a byte which represents the states of the 3 digital input and 3 digital output states. Bits 3-5 correspond to the states of digital inputs 0-2. Bits 0-2 correspond to the states of digital outputs 0-2. If a bit is a 0 then the digital state of that digital I/O is LOW. If a bit is a 1 then the digital state of the I/O is HIGH. Refer to Table 3.4 and 3.5.

Command Syntax

!{addr}RD

Unit Response

{states}

Where {states} is a byte in which Bits 0-2 corresponds to the current states of Digital Outputs 0-2 and Bits 3-5 corresponds to the current states of Digital Inputs 0-2.

Table 3.4 - Read Digital I/O Response for Outputs

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