330
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
13 High Speed Processing – FNC 50 to FNC 59
13.4 FNC 53 – HSCS / High Speed Counter Set
3. Specification of output numbers (Y)
When using a same instruction for high speed counter repeatedly or when driving two or more other
instructions for high speed counter at the same time, specify such output devices (Y) whose high-order two
digits are the same (in units of 8 devices).
1) When using devices of a same number (in units of 8 devices)
Example: When using Y000, specify Y000 to Y007. When using Y010, specify Y010 to Y017.
2) When using two or more instructions for high speed counter and non-consecutive output (Y) numbers
A program example is shown below:
When C255 reaches K100, the output Y000 is driven by interrupt. Y010 is driven when END processing
is executed.
If interrupt drive is required, use an output number in the range from Y001 to Y007 whose high-order two
digits are equivalent.
4. Caution on the counting operation when the current value is changed
An instruction for high speed counter gives the comparison result when a pulse is input to the input (X) for
high speed counter.
However, the comparison result is not given when the current value of high speed counter is changed in the
following method:
1) Change method (examples)
a) Overwriting the contents of a word device used as the comparison value using DMOV instruction, etc.
b) Resetting the current value of a high speed counter in a program
2) Operation
Even if the condition for setting the output to ON or OFF is given as the comparison result, the
comparison result does not change when an instruction is simply driven.
5. Reset operation by an external terminal [M8025
*1
: HSC (external reset) mode]
For a high speed counter equipped with an external reset terminal (R) such as C241, an instruction is
executed and the comparison result is output at the rising edge of the reset input signal.
1) Program
If an instruction for high speed counter is used while M8025
*1
is driven, the instruction is executed again
when the current value of the high speed counter C241 is cleared by an external reset terminal. And the
comparison result is output even if a counting input is not given.
*1.
M8025 is cleared when the PLC mode is changed from RUN to STOP.
2) Operation
When the external reset input X001 turns ON while the current value of C241 is "100", for example, the
current value of C241 is reset to "0". And Y000 is reset at this time even if a counting input is not given.
FNC 53
DHSCS
K100
C255
Y010
FNC 53
DHSCS
K100
C255
Y000
M8000
External reset
terminal for C241
M8025 *1 External reset mode
FNC 54
DHSCR
K 0
C241
Y000
C241
K9,999
M8000
RUN monitor
X001
