KEYENCE Visual KV Series - Manual (Page 311)

6.2 High-speed Counters
KV
-300
KV-10/80
3-287
1 6
Chapter 6 Interrupts, High-speed Counters, Positioning Control
0000 2204
0000
SET
2204
RES
0000
2204
0000
SET
RES
KEEP
KEEP Instructions SET/RES Instructions
When start/stop of clock pulse is controlled by the input relay which enables/
disables the high-speed counter, response relay of up to 1 scan is generated
at start. Also, the same response relay is generated at stop, which may stop
clock pulse output while the output relay is still ON.
This controls clock pulse so that it always starts and stops when 2204 turns OFF.
Turn ON/OFF special utility relay 2204 as required to enable or disable output of
direct clock pulses using one of the external clocks. Use SET and RES instructions
together or only KEEP instruction to turn ON/OFF this relay.
The diagram below can be added to the sample diagram so that direct clock pulses
are output through 0501 only when 0000 is ON.
CAUTION
Example of clock pulse with variable ON/OFF ratio
■ When outputting clock pulse with cycle 500 µs (2 kHz) and pulse width
200 µs from 0500
This program example shows how to output clock pulse varies ON/OFF ratio from
0500, through high-speed counter CTH0 and high-speed counter comparator
CTC0 and CTC1.
Setting special utility relays
Special utility relays 2103 to 2112 are set as shown in the table below.
Values set to the internal clock, CTC0 and CTC1
After the internal clock is determined, the CTC0 and CTC1 setting value is calcu-
lated from the following expression.
CTC1 setting value = Pulse width (µs) ÷ Internal clock (µs)
CTC0 setting value = Pulse cycle (µs) ÷ Internal clock (µs)
Assign 200 µs to pulse width, 500 µs to pulse cycle and 10 µs (2101: special utility
relay) to internal clock and calculate the CTC0 and CTC1 setting value.
The calculated results of CTC1 and CTC0 are "20" and "50", respectively.
Values calculated based on other internal clocks are listed below for your reference.
Special utility relay Internal clock* CTC0 value CTC1 value
2100 1.0 µs 500 200
2101 10.0 µs 50 20
2102 100.0 µs 5 2
➮ * Refer to page 3-276.
Relay No. Setting Relay No. Setting
2103 ON 2112 OFF
2104 OFF 2108 OFF
2105 OFF 2109 ON
2106 ON 2110 OFF
2107 OFF 2111 OFF
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