Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers - Manual (Page 199)

Using Application Specific Instructions
11–11
The following figure indicates how the SQO instruction works.
SQO
SEQUENCER OUTPUT
File
#B3:1
Mask 0F0F
Dest O:0
Control R6:05
Length 4
Position 2
(EN)
(DN)
0000 0101 0000 1010
0 7 8 15
0000 1111 0000 1111
0 7 8 15
0000 0000 0000 0000
1010 0010 1111 0101
1111 0101 0100 1010
0101 0101 0101 0101
0000 1111 0000 1111
0
1
2
3
4
Step
B3:1
2
3
4
5
Word
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
ON
ON
ON
ON
External Outputs
Associated with O:0
Destination O:0.0
Mask Value 0F0F
Sequencer Output File #B3:1
Current Step
Using SQC
When the status of all non-masked bits in the source word match those of the
corresponding reference word, the instruction sets the found bit (FD) in the control
word. Otherwise, the found bit (FD) is cleared.
The bits mask data when reset and pass data when set.
The mask can be fixed or variable. If you enter a hexadecimal code, it is fixed. If
you enter an element address or a file address for changing the mask with each step,
it is variable.
When the rung goes from false-to-true, the instruction increments to the next step
(word) in the sequencer file. Data stored there is transferred through a mask and
compared against the source for equality. While the rung remains true, the source is
compared against the reference data for every scan. If equal, the FD bit is set in the
SQCs control counter.
Programming