Pulse Catch Function [M8170 To M8177] - Mitsubishi Electric MELSEC FX3U Programming Manual

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
6. Cautions
1) Pointer number
Pointer numbers cannot overlap with each other.
2) Disabling interrupts
When the special auxiliary relay M8059 is set to ON in a program, all counter interrupts are disabled.
36.7

Pulse Catch Function [M8170 to M8177]

When the input relay X000 to X007 turns ON from OFF after the FNC 04 (EI) instruction is executed, the
special auxiliary relay M8170 to M8177 is set for interrupt processing.
The FNC04 (EI) instruction is not required in FX
1. Assignment of input numbers and special auxiliary relays
Pulse catch input
X000
X001
X002
X003
X004
X005
X006
X007
*1. Cleared when the PLC mode is changed from STOP to RUN.
*2. This function is supported only in FX
2. Program example
Step
0
M8170
X002
Reset input
EI
X000(Input)
M8170
X002(Reset)
FX /FX PLC
3U 3UC
[X000 to X005]: 5 µs or more
[X006 and X007]: 50 µs or more
PLCs.
3G
Pulse catch relay
*1
M8170
*1
M8171
*1
M8172
*1
M8173
*1
M8174
*1
M8175
*1*2
M8176
*1*2
M8177
/FX
3U 3UC
FNC 04
The FNC04 (EI) instruction is not required in FX
EI
When the rising edge of X000 is detected,
Y000
M8170 is set as interrupt.
The pulse catch result is reset.
RST M8170
Input pulse width
(shown below)
FX PLC
3G
[X000, X001, X003 and X004]: 10 µs or more
*1
[X002 and X005]: 50 µs or more
36 Interrupt Function and Pulse Catch Function
36.7 Pulse Catch Function [M8170 to M8177]
PLCs.
31
32
33
34
35
36
PLCs.
3G
37
38
A
B
867