Yaskawa FSP Amplifier FlexWorks - Manual (Page 90)

Operating the FSP Amplifier Using FlexWorks
90
4.11.4. Interrupt Masks
Using masks, you can specify which interrupt events need be
handled, and which need not be. This allows you to specify
interrupt service routines for a number of possible events, and then
to deactivate them from within the program as required.
If no mask is specified, the program will not react to any interrupt
event. An interrupt mask must therefore always be specified if
interrupts are to be used.
See Section 4.11.6.2, Interrupt_mask.
4.11.5. Interrupt Handling
The process that occurs when an interrupt occurs is summarized
below. Detailed instructions on the use of the various variables and
commands are provided in the sections that follow.
♦ Event Occurs:
External event, such as a change in an input value
Or
Internal event, such as a system variable meeting some
condition.
♦ Interrupt is registered:
The relevant bit of variable Interrupt_request is set to 1.
♦ If the registered interrupt is masked in Interrupt_mask, the
program flow is interrupted:
The FSP Amplifier stops retrieving commands from the
user program buffer.
♦ The FSP Amplifier executes the interrupt service routine for
the highest priority interrupt received.
♦ The FSP Amplifier clears the relevant bit in the variables
Interrupt_request and Interrupt_pending to indicate that the
interrupt has been cleared.
♦ The FSP Amplifier executes the interrupt service routines for
any other outstanding interrupts, in order of priority.
♦ The FSP Amplifier continues running the program:
Either from the program line where it was initially
interrupted
Or
From another location specified in the interrupt service
routine.