Chapter 19
Comparison Instructions
19–8
MASKED EQUAL
Source
B3:10
0100011100000000
Mask
00FF
Compare
B3:11
0000000001110101
Masked Comparison for Equal
MEQ
Input Instruction
MEQ
MEQ
F1
F2
F3
F4
F5
ZOOM on MEQ –|MEQ|– 2.3.0.0.1
NAME: MASKED EQUAL
SOURCE A: B3:10 0100 0110 0000 0000
MASK: 00FF 00FF
COMPARE: B3:11 0000 0000 0111 0101
EDT_DAT
HHT Ladder Display:
HHT Zoom Display:
Ladder Diagrams and APS Displays:
(online monitor mode)
This input instruction compares data at a source address with data at a
reference address and allows portions of the data to be masked by a separate
word.
Entering Parameters
•
Source – the address of the value you want to compare.
•
Mask – a hex value or the address of the mask through which the
instruction moves data. Refer to appendix B for more information
regarding masks and hexadecimal numbering.
•
Compare – 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.
Masked Comparison for
Equal (MEQ)