The 2nd cell contains the interrupt number for the interrupt type.
SPI interrupts are in the range [0-987]. PPI interrupts are in the
- range [0-15]. Extented SPI interrupts are in the range [0-1023].
+ range [0-15]. Extended SPI interrupts are in the range [0-1023].
Extended PPI interrupts are in the range [0-127].
The 3rd cell is the flags, encoded as follows: