KEYENCE Visual KV Series - Manual (Page 248)

4.4 Expanded Functions of High-speed Counters
3-224
Visual KV
Series
4
Chapter 4 High-speed Counters
4.4.3 Application Example of 24-bit High-speed Counter
(single-phase input)
The following is a ladder program using a 24-bit high-speed counter and high-speed
counter comparator with a preset value of "1000000".
1) Sets CTH0 as the 24-bit high-speed counter with the MEWSW instruction. (Turn
on 3 of SW3.)
2) When power is turned on, writes the preset value "1000000" of the high-speed
counter comparator (CTC0) and sets the value with the STA CTC0 instruction.
3) Sets the input time constant of input relay 0004 to 10 µs.
4) Counts pulses at input relay 0004 with high-speed counter CTH0.
5) Defines a dummy high-speed counter comparator.
6) Reads the current value of CTH0 into data memory DM0000 (low-order bits) and
DM0001 (high-order bits) each scan time.
2008 CTH0
RES
0008
CTC0
STA
DM1916
STA
#16960
LDA
DM1917
STA
#00015
LDA
2002 DM0000
STA
DM1900
LDA
DM0001
STA
DM1901
LDA
2002
0002
0001
HSP
0004
2002
0003
0004
CTH0
0004
0006
END
0007
0005
ENDH
#65535
CTC0
2)
1)
3)
4)
5)
6)
MEMSW
$0800
Low-order 16 bits of
current value of high-
speed counter
High-order 16 bits of
high-speed counter
comparator Low-order 16 bits of
high-speed counter
comparator Writes preset value of
high-speed counter
comparator
High-order 16 bits of
current value of high-
speed counter
KVNKA Chap 04_1.p65 08.3.11, 0:06 PM 224