Mitsubishi Electric MELSEC FX Series - 8.5.2 Example of practical program (timer interrupt program using instruction)

8 Interrupt Function and Pulse Catch Function
8.5 Timer Interrupt (Interrupt in Constant Cycle)
820
FXCPU Structured Programming Manual
(Basic & Applied Instruction)
6. Program example
In the program example shown below, data is added and addition result is compared with the set value at
every 10 ms.
1) Program example
8.5.2 Example of practical program (timer interrupt program using instruction)
RAMP, HKY, SEGL, ARWS and PR instructions execute a series of operations in synchronization with the
scan time.
Because the total time may be too long or time fluctuation may cause a problem in these instructions, it is
recommended to execute these instructions at a constant time interval using the timer interrupt function.
When not using the timer interrupt function, use the constant scan mode.
1. Timer interrupt processing of HKY instruction
EI
EN ENO
FEND
EN ENO
M3
Interrupts are enabled by EI instruction.
The main program is described.
The main program is finished by FEND instruction.
When the current value of D0 reaches "1000", M3 is reset.
M3
SET
EN ENO
d
X001
INC
EN ENO
d
LD-EQ
EN
s1
s2
ENO
RST
EN ENO
d
K1000
D0
M3
D0
When M3 is set to ON, INC instruction becomes valid.
"1" is added to the current value of D0 at every 10 ms.
The current value of D0 is ramp data which changes from
"0" to "1000" in 10 seconds.
In the program example using RAMP instruction shown
later, the ramp data is made using a dedicated instruction.
When interrupt is
given at every 10 ms
[Main program]
[Interrupt program]
(Event: I610)
EI
EN ENO
FEND
EN ENO
Interrupts are enabled by EI instruction.
The main program is described.
The main program is finished by FEND instruction.
M8000
HKY
EN
s
ENO
d1
d3
d2
Y000
D0
M0
X000
REF
EN
d
n
ENO
X000
K8
REF
EN
d
n
ENO
Y000
K8
[Main program]
[Interrupt program]
(Event: I620)