15.13 Interrupts

Interrupts can be classified into multiple layers. Lower layer interrupts propagate to higher layers by multiplexing them into single interrupts. Figure 15-48 illustrates the layers of interrupts.

FIFO Individual Interrupt
FIFO Combined Interrupt
Main Interrupt

These interrupts are then funneled into three separate module interrupts:

Receive Interrupt
Transmit Interrupt
Information Interrupt

All module interrupts are persistent, meaning the condition that caused the interrupt must be cleared within the module for the interrupt request to be removed.

Figure 15-48. Interrupt Multiplexing