Version 1.0, August 31, 2001, Copyright, Hugh Jack 1993-2001
· To input analog values into a PLC we use the block transfer commands. These allow control information to the input card and retrieve results.
· The example below shows ladder logic to do an analog input.
· The block that needs to be written to an 1771-IFE analog input card is shown below. This is a 12 bit card, so the range will have up to 2**12 = 4096 values.
· After the input card reads the values, the results are returned in a block. The structure of the block is shown below.
