Omron SYSMAC C2000H Operation Manual page 195

Subroutines and Interrupt Control
Interrupt Priority Levels
When an interrupt is being serviced (i.e. the subroutine is executing), another
incoming interrupt must wait until the first is finished before it will be serviced.
Interrupt input #1
Interrupt #1 servicing
Interrupt input #2
Interrupt #2 servicing
If two or more interrupt inputs are turned ON simultaneously, the subroutine
with the lowest subroutine number takes precedence. For example, interrupts
from interrupt Unit 0, bit 0 will be serviced before interrupts from Unit 2, bit 3.
Subroutines for interrupts from Interrupt Input Units will be interrupted for the
scheduled interrupt.
Section 5-20
189