Applications of inc/dec instructions – KEYENCE Visual KV Series User Manual
Page 197

2.4 Instruction Details
1
2
3-173
Chapter 2 Instructions
Key operation
Arithmetic flag
2009
Turns ON when the result is "0" after an INC operation, or when the
result is "$FFFF (#65535)" after DEC operation. Turns OFF at other
times.
2010
Turns ON when the internal register is "0" after an INC or DEC opera-
tion. Turns OFF at other times.
2011, 2012 No change
Note: When an every-scan type INC/DEC instruction is used, INC (+1) or DEC (-1)
instruction is executed every scan time while input relay 0000 is ON.
Use a differentiation type instruction (@INC or @DEC) to execute the instruction
only once when input relay 0000 turns ON, as shown in the example.
Tips
When using DM0000 as an UP/DOWN counter
Performs an UP count (addition) when input relay 0000 turns ON.
Performs a DOWN count (subtraction) when input relay 0001 turns ON.
Applications of INC/DEC instructions
■ UP/DOWN count
Performs an UP count when input relay 0000 turns ON.
Performs a DOWN count when input relay 0001 turns ON.
Writes the count value into DM0000.
Reset input relay is 0005.
Coding
0000
DM0000
INC
0001
DM0000
DEC
#00000
LDA
2008
0000
DM0000
STA
0005
#00000
DW
DM0000
INC
0001
DM0000
DEC
DM0000
0000
DM0000
INC
0000
DM0000
INC
Clears DM0000 to #00000 when 0005
turns ON.
Sets #00000 to DM0000 at startup.
Increments DM0000 by 1 at UP edge
of input relay 0000.
Decrements DM0000 by 1 at UP edge
of input relay 0001.
@
#,$
FUN
FUN
@
#,$
FUN
FUN
SET
1
O R
9
L D
7
RES
0
ENT
R-SRCH
ENT
R-SRCH
Operand
ENT
R-SRCH
ENT
R-SRCH
Operand
Line No.
Instruction
Operand
Line No.
Instruction
Operand
0000
LD
2008
0005
@INC
DM0000
0001
LDA
#00000
0006
LD
0001
0002
CON
0007
@DEC
DM0000
0003
STA
DM0000
0008
LD
0005
0004
LD
0000
0009
DW
#00000 DM0000
INC / @INC / DEC / @DEC
KVNKA Chap 02_4dP.p65
08.3.11, 0:03 PM
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