13: P
ROGRAM
B
RANCHING
I
NSTRUCTIONS
13-2
FC6A S
ERIES
MICROS
MART
L
ADDER
P
ROGRAMMING
M
ANUAL
FC9Y-B1726
Example: LJMP and LABEL
The following example demonstrates a program that jumps to three different portions of the program depending on the input.
Using the Timer Instruction with Program Branching
When the timer start input of the TML, TIM, TMH or TMS instruction is already on, countdown begins immediately at the location
jumped to, starting with the timer current value. When using a program branch, it is important to make sure that timers are
initialized when desired, after the jump. If it is necessary to initialize the timer instruction (set to the preset value) after the jump,
the timer’s start input should be kept off for one or more scan cycles before initialization. Otherwise, the timer input on will not be
recognized.
Using the SOTU/SOTD Instructions with Program Branching
Check that pulse inputs of counters and shift registers, and inputs of single outputs (SOTU and SOTD) are maintained during the
jump, if required. Hold the input off for one or more scan cycles after the jump for the rising or falling edge transition to be
recognized.
LABEL
0
I0
LJMP
S1
0
END
I1
LJMP
S1
1
I2
LJMP
S1
2
M8121
END
M8122
END
M8123
END
Q0
Q1
Q2
LABEL
1
LABEL
2
When input I0 is on, program execution jumps to label 0.
When input I1 is on, program execution jumps to label 1.
When input I2 is on, program execution jumps to label 2.
M8121 is the 1-s clock special internal relay.
When jump occurs to label 0, output Q0 oscillates in 1-s increments.
M8122 is the 100-ms clock special internal relay.
When jump occurs to label 1, output Q1 oscillates in 100-ms increments.
M8123 is the 10-ms clock special internal relay.
When jump occurs to label 2, output Q2 oscillates in 10-ms increments.
Although normally, the SOTU instruction produces a pulse for
one scan, when used in a program branch the SOTU pulse will
last only until the next time the same SOTU instruction is
executed.
In the example on the left, the program branch will loop as long
as internal relay M0 remains on. However, the SOTU produces a
pulse output only during the first loop.
Since the END instruction is not executed as long as M0 remains on, output Q1 is not turned on even if input I1 is on.
I1
SOTU
M0
LJMP
S1
0
Q1
LABEL
0
Q1 Internal
ON
OFF
Q1 Output
ON
OFF
Memory
END
END
Summary of Contents for MICROSmart FC6A Series
Page 1: ...B 1726 7 FC6A SERIES Ladder Programming Manual ...
Page 8: ...Preface 7 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 32: ...1 OPERATION BASICS 1 20 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 96: ...3 INSTRUCTIONS REFERENCE 3 18 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 130: ...4 BASIC INSTRUCTIONS 4 34 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 192: ...9 SHIFT ROTATE INSTRUCTIONS 9 12 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 272: ...12 DISPLAY INSTRUCTIONS 12 24 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 284: ...14 REFRESH INSTRUCTIONS 14 6 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 502: ...25 DATA LOG INSTRUCTIONS 25 22 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 546: ...26 SCRIPT 26 44 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...
Page 598: ...APPENDIX A 14 FC6A SERIES MICROSMART LADDER PROGRAMMING MANUAL FC9Y B1726 ...