AND

The AND logic function evaluates the state of two integers.

• If a bit is true (logic 1) in both input A and B, then the output C will be true (logic 1).

• If input A and B is false (logic 0), then the output C will be false (logic 0).

• If either input A or B is false (logic 0) - the output C will be false (logic 0).

The input values in an AND function may be:

• Memory Integer (MI)

• Memory Long Integer (ML)

• Double Word (DW)

• System Operands:(SI) (SL) (SDW)

• Network System Integer (NSI)

• Constant Value #

With the exception of Constant Value, any of these operands may be used to contain the output value.

AND can be used to mask out certain bits of an input integer not relevant to a given function.

Example:

If a clock function block uses the first bit of a 16-bit word to decide if a given time is A.M. or P.M., you can mask out the other 15 bits. This will tell you if the current time is A.M. or P.M.

All of the non-relevant bits will be turned off (logic 0) except the A.M. / P.M. bit.

The function is located under the Logic menu on the Ladder toolbar.