Peripheral Interrupt Expansion (PIE)
The peripheral interrupt expansion (PIE) block multiplexes numerous interrupt sources into a smaller set of interrupt inputs. The PIE block can support 96 individual interrupts that are grouped into blocks of eight.
Each group is fed into one of 12 core interrupt lines (INT1 to INT12). Each of the 96 interrupts is supported by its own vector stored in a dedicated RAM block that you can modify. The CPU, upon servicing the interrupt, automatically fetches the appropriate interrupt vector. It takes nine CPU clock cycles to fetch the vector and save critical CPU registers. Therefore, the CPU can respond quickly to interrupt events. Prioritization of interrupts is controlled in hardware and software. Each individual interrupt
can be enabled/disabled within the PIE block.