Mitsubishi Electric MELSEC FX3U Programming Manual page 379

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
2. Device specification range
Only high speed counters (C235 to C255) can be specified as
3. Only 32-bit operation instructions are available.
Because instructions for high speed counters are dedicated to 32 bits, make sure to input "DHSZ (FNC 55)".
4. Caution on values set in the comparison value 1
Make sure that
5. Relationship between the comparison timing and the result output
1) DHSZ instruction executes comparison and outputs the result only when a counting pulse is input to a
high speed counter.
(When
S
1
C235 changes from "999" to "1000" or from "1999" to "2000".)
2) Because the comparison result cannot be obtained when restoring the power or when the PLC mode
switches from STOP to RUN, the result is not output even if the comparison condition is provided.
→ For details, refer to "13.6.1 Program in which comparison result is set to ON when power is turned
6. Priority order in operation among HSCS (FNC 53), HSCR (FNC 54), and HSZ (FNC 55)
instructions for a same high speed counter
→ For details, refer to "6. Priority order in operation among HSCS (FNC 53), HSCR (FNC 54), and HSZ
7. Reset operation by an external terminal
→ For details, refer to "5. Reset operation by an external terminal [M8025*1: HSC (external reset)
8. Number of occupied devices
1) The comparison value occupies two devices from
2) The output occupies three devices from
is smaller than or equivalent to
S
1
is "1000" and is "1999", the output
S
2
(FNC 55) instructions for a same high speed counter" in Subsection 13.4.1.
13 High Speed Processing – FNC 50 to FNC 59
13.6 FNC 55 – HSZ / High Speed Counter Zone Compare
.
S
and comparison value 2
S
1
.
S
2
is set to ON as soon as the current value of
D
or respectively.
S S
1 2
.
D
S
2
ON [ZCP (FNC 11) instruction]".
mode]" in Subsection 13.4.1.
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