Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers - Manual (Page 127)

Using Comparison Instructions
7–5
Masked Comparison for Equal (MEQ)
Use the MEQ instruction to compare data of a source address with data of a
reference address. Use of this instruction allows portions of the data to be masked
by a separate word.
Entering Parameters
•
Source is the address of the value you want to compare.
•
Mask is the address of the mask through which the instruction moves data. The
mask can be a hexadecimal value (constant).
•
Compare is an integer value or the address of the reference.
If the 16 bits of data at the source address are equal to the 16 bits of data at the
compare address (less masked bits), the instruction is true. The instruction becomes
false as soon as it detects a mismatch. Bits in the mask word mask data when reset;
they pass data when set.
Programming
Execution Times
(
µ
sec) when:
True False
28.39 7.69
MEQ
MASKED EQUAL
Source
Mask
Compare