333
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
13 High Speed Processing – FNC 50 to FNC 59
13.5 FNC 54 – HSCR / High Speed Counter Reset
11
FN
C30-
FN
C39
R
o
ta
tion and
Sh
ift
12
FNC
4
0
-FNC49
D
a
ta
Op
e
ra
tio
n
13
FNC5
0
-FNC5
9
H
igh Speed
Pr
ocessi
ng
14
FM
C6
0
-F
NC6
9
H
and
y
In
st
ru
cti
o
n
15
FNC7
0
-FNC7
9
Ex
te
rn
a
l F
X
I
/O
D
evi
ce
16
FNC8
0
-FNC8
9
Ext
e
rnal
FX
D
evi
ce
17
F
N
C1
00
-F
NC
10
9
Da
ta
Tr
ansf
e
r 2
18
FN
C
110-FN
C
13
9
Fl
oat
ing P
o
in
t
19
FN
C
140-FN
C
149
Da
ta
O
per
at
io
n
2
20
FN
C
15
0-F
N
C
159
P
o
si
tioni
ng
C
ont
ro
l
Operation
When the present value of the high speed counter C255 changes (counts) from "99" to "100" or from "101" to
"100", Y010 is reset (output refresh).
Related instructions
The following instructions can be combined with high speed counters:
Cautions
1. Selection of the count comparison method
When HSCR instruction is used, hardware counters (C235, C236, C237, C238, C239, C240, C244 (OP),
C245 (OP), C246, C248 (OP), C251 and C253) are automatically switched to software counters, and the
maximum frequency of each counter and the total frequency are affected.
Refer to the counting operation described below, and select according to the contents of control whether to
use HSCR instruction or general-purpose comparison instruction.
1) Case to select HSCR instruction
- When the output should be given when the counting result becomes equivalent to the comparison value
without regard to the scan time of the PLC
2) Cases to select a general-purpose comparison instruction
- When the required frequency is beyond the counting performance of software counters
- When counting is regarded important, but the effect of the scan time can be ignored in operations
according to the counting result
- When the number of an instruction is more than 32
2. Only 32-bit operation instructions are available.
Because instructions for high speed counters are dedicated to 32 bits, make sure to input "DHSCR (FNC 54)".
3. Priority order in operation among HSCS (FNC 53), HSCR (FNC 54), and HSZ (FNC 55)
instructions for a same high speed counter
→
For the details, refer to "6. Priority order in operations among HSCS (FNC 53), HSCR (FNC 54), and
HSZ (FNC 55) instructions for the same high speed counter" in Subsection 13.4.1.
4. Reset operation by an external terminal
→
For the details, refer to "5. Reset operation by an external terminal [M8025*1: HSC (external reset)
mode]" in Subsection 13.4.1.
Instruction
FNC No.
Instruction name
DHSCS
FNC 53
High speed counter set
DHSCR
FNC 54
High speed counter reset
DHSZ
FNC 55
High speed counter zone compare
DHCMOV
FNC189
High speed counter move
DHSCT
FNC280
High speed counter compare with data table
K100 = C255
→
Y010
C255
K2,147,483,647
FNC 54
DHSCR
K100
C255
Y010
Reset.
Comparison
value
Comparison
source
Output
destination
M8000
RUN
monitor
M8000
FNC189
DHCMOV
C251
D100
K0
RST
Y010
FNC230
LD
≥
K10000
D100
M8000
FNC 50
REF
Y010
K8