Mitsubishi Electric MELSEC FX Series - Page 292

7 Applied Instructions
7.6 High Speed Processing
290
FXCPU Structured Programming Manual
(Basic & Applied Instruction)
Related instruction
The following instructions can be combined with high speed counters.
Cautions
1. Selection of the counter comparison method
When the DHSCS instruction is used, the maximum frequency and total frequency of the high speed counter
are affected.
Refer to the counting operation described below, and select according to the contents of control whether to
use this instruction or general-purpose comparison instruction.
1) Case to select DHSCS 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.
- When counting is regarded as important, but the effect of the scan time can be ignored in operations
according to the counting result.
- When the number of an instruction exceeds the allowable limit.
For FX
3U and FX3UC PLCs
Instruction Instruction name
DHSCS High speed counter set
DHSCR High speed counter reset
DHSZ High speed counter zone compare
DHCMOV High speed counter move
DHSCT High speed counter compare with data table
M8000
LDD>
EN
s1
s2
ENO
LDD<=
EN
s1
s2
ENO
LDD<
EN
s1
s2
ENO
DHCMOV
EN
s
n
ENO
Label 1
*1
0
*1. This defines CN251.
*2. This defines D100.
REF
EN
d
n
ENO
K8
Y10
d
Label 2
*2
Label 3
*3
Label 4
*4
Label 5
*5
Label 6
*6
ANDD<=
EN
s1
s2
ENO
Label 7
*7
Label 8
*8
Label 9
*9
Label 10
*10
M8000
Y011
Y012
Y010
*3. This defines K10000.
*4. This defines D100.
*5. This defines K10000.
*6. This defines D100.
*7. This defines K20000.
*8. This defines D100.
*9. This defines K20000.
*10. This defines D100.