Allen-Bradley micrologix 1500 Reference Manual

Publication 1762-RM001C-EN-P
9-6 Compare Instructions
MEQ - Mask Compare
for Equal
Instruction Type: input
The MEQ instruction is used to compare whether one value (source) is
equal to a second value (compare) through a mask. The source and the
compare are logically ANDed with the mask. Then, these results are
compared to each other. If the resulting values are equal, the rung state is
true. If the resulting values are not equal, the rung state is false.
For example:
The source, mask, and compare values must all be of the same data size
(either word or long word). The data ranges for mask and compare are:
•
-32768 to 32767 (word)
•
-2,147,483,648 to 2,147,483,647 (long word)
The mask is displayed as a hexadecimal unsigned value from 0000 to
FFFF FFFF.
MEQ
Masked Equal
Source N7:0
0<
Mask N7:1
0000h<
Compare N7:2
0<
MEQ
Table 9.8 Execution Time for the MEQ Instructions
Controller Data Size When Rung Is:
True False
MicroLogix 1200 word 1.9
µ
s1.8
µ
s
long word 3.9
µ
s3.1
µ
s
MicroLogix 1500 word 1.7
µ
s1.7
µ
s
long word 3.5
µ
s2.9
µ
s
Source: Compare:
11111010000011001111111100000000
Mask: Mask:
11001111110000111100111111000011
Intermediate Result: Intermediate Result:
11001010000000001100111100000000
Comparison of the Intermediate Results: not equal

Allen-Bradley micrologix 1500 Specifications

General

Brand	Allen-Bradley
Model	micrologix 1500
Category	Controller
Language	English