Texas Instruments Tiva TM4C123GH6PM, User Manual

Page: 144 / 352

Interrupt Controller (NVIC)
ROM Location:
ROM_APITABLE
is an array of pointers located at
0x0100.0010
.
ROM_INTERRUPTTABLE
is an array of pointers located at
ROM_APITABLE[14]
.
ROM_IntPrioritySet
is a function pointer located at
ROM_INTERRUPTTABLE[6]
.
Parameters:
ui32Interrupt specifies the interrupt in question.
ui8Priority specifies the priority of the interrupt.
Description:
This function is used to set the priority of an interrupt. When multiple interrupts are asserted
simultaneously, the ones with the highest priority are processed before the lower priority in-
terrupts. Smaller numbers correspond to higher interrupt priorities; priority 0 is the highest
interrupt priority.
The hardware priority mechanism will only look at the upper 3 bits of the priority level, so
any prioritization must be performed in those bits. The remaining bits can be used to sub-
prioritize the interrupt sources, and may be used by the hardware priority mechanism on a
future part. This arrangement allows priorities to migrate to different NVIC implementations
without changing the gross prioritization of the interrupts.
Returns:
None.
144 April 8, 2013