Mitsubishi FX3U Series, Руководство по программированию

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581
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
24 Others – FNC181 to FNC189
24.5 FNC189 – HCMOV / High Speed Counter Move
21
FN
C
160-FN
C
169
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C
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C
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22
FN
C
170
-F
N
C
17
9
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23
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C
180
Su
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24
FN
C
181-FN
C
189
O
ther
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25
FN
C
190-FN
C
19
9
B
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26
FN
C
200-FN
C
209
C
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C
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27
F
N
C2
10
-F
NC
21
9
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ta O
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28
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220-FN
C
24
9
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29
FN
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250-FN
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269
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30
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27
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274
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2. High speed counter current value update timing and the effect of DHCMOV instruction
1) High speed counter current value update timing
When a pulse is input to the input terminal for a high speed counter (C235 to C255), the high speed
counter executes up counting or down counting. Its current value is updated at the timing shown in the
table below.
When the current value of a high speed counter is handled in an applied instruction such as the normal
MOV instruction, the current value updated at the timing below is used. As a result, it is affected by scan.
By using DHCMOV instruction, the current value can be updated and transferred when it is executed.
2) Effect of DHCMOV instruction
• By using both input interrupt and DHCMOV instruction, the current value of a high speed counter can
be received at the rising edge or falling edge of an external input (at reception of input interrupt).
→
Refer to the Program example 2.
• When DHCMOV instruction is used just before a comparison instruction (CMP, ZCP or comparison
contact instruction), the latest value of a high speed counter is used in comparison. DHCMOV
instruction has the following effect which cannot be given by comparison instructions for high speed
counter.
- When the current value of a high speed counter is compared using CMP, ZCP or comparison
contact instruction (not using a comparison instruction for high speed counter), a hardware counter
does not change into a software counter.
→
For the condition in which a hardware counter is handled as a software counter,
refer to Subsection 4.7.9.
- When the number of a comparison instruction for a high speed counter can be reduced for software
counters, the limitation in the total frequency is mitigated.
→
For the limitation in software counters by the total frequency,
refer to Subsection 4.7.10.
- When it is necessary to execute comparison and change an output contact (Y) as soon as the
current value of a high speed counter changes, use a comparison instruction for a high speed
counter (HSCS, HSCR or HSZ).
- DHCMOV instruction can be used as many times as necessary.
Current value update timing
Hardware counter When OUT instruction for the counter is executed
Software counter Every time a pulse is input