USER MANUAL APS 6.0
Ladder Logic Program Basics
4–13
The
diagram above is the same one that appears on the
preceding page. This diagram is also represented below
,
with each instruction replaced with a T or F
, indicating the
initial T
rue/False status of the instruction.
The table at the right indicates how the instructions are
executed when XIC instruction I:0/1 changes state. (I:0/1
represents an external momentary contact push button.)
TTFF
TTTT
F
T T
T T
]/[
B3
10
] [
I:0
1
( )
B3
11
( )
B3
12
] [
B3
11
]/[
B3
12
]/[
B3
10
( )
O:0
2
( )
B3
10
] [
I:0
1
] [
B3
11
] [
B3
11
] [
I:0
1
TFTF
TFTT
T
T T
T T
FTFF
FTTF
F
F F
F F
Instruction
Execution
T = true at time of execution
F = false at time of execution
XIC
I:0/1
Goes
True
Goes
False
Scan 1000 Scan 1001
FFTF
FFTT
T
F F
T T
FTTF
FTTT
T
F F
T T
Scan 2000 Scan 2001
TTTT
TTFF
T
T T
F F
TFFF
TFTF
F
T T
F F
Scan 3000 Scan 3001
FFFF
FFTF
F
F F
F F
FTFF
FTTF
F
F F
F F
Scan 4000 Scan 4001
Goes
False
Goes
True