Timer Interrupt - IDEC FT1A Series User Manual

Timer Interrupt

In addition to the interrupt input as described in the preceding section, all SmartAXIS have a timer interrupt function. When a
repetitive operation is required, the timer interrupt can be used to call a subroutine repeatedly at predetermined intervals of 10
through 140ms.The timer interrupt can only be used when ladder program is selected as the programming language.
The Function Area Settings dialog box is used to enable the timer interrupt and to specify the interval, from 10 to 140ms, to
execute the timer interrupt. When the timer interrupt is enabled, the program execution repeatedly jumps to the jump destination
label number stored in special data register D8036, while the SmartAXIS is running. When the interrupt program is completed, the
program execution returns to the main program at the address where the interrupt occurred.
Since these settings relate to the user program, the user program must be downloaded to the SmartAXIS after changing any of
these settings.
Special Data Register and Special Internal Relay for Timer Interrupt
Interrupt
Timer Interrupt
Note: A label is the starting address of the program branch to jump to, and it is specified by the LABEL instruction.
Programming WindLDR
From the WindLDR menu bar, select Configuration > Input Configuration.
1.
The Function Area Settings dialog box for Input Configuration appears.
Under the Timer Interrupt, click the check box to use the timer interrupt function.
2.
3. Select an interval to execute the timer interrupt, from 10 to 140ms.
Disable and Enable Interrupts
The timer interrupt and interrupt inputs I0, I2, I3, and I5 through I7 are normally enabled while the SmartAXIS is running, and can
also be individually disabled using the DI instruction or enabled using the EI instruction. When timer interrupt is enabled, M8144 is
turned on. When disabled, M8144 is turned off. See Chapter 16 "Interrupt Control Instructions" in the "SmartAXIS Ladder
Programming Manual".
Special Data Register for Timer Interrupt Jump
Destination Label No.
D8036
S AXIS P
MART RO
/L U ' M FT9Y-B1378
ITE SER S ANUAL
5: S F
PECIAL
Special Internal Relay for
Timer Interrupt Status
M8144
UNCTIONS
5-41