
Interrupts UM018809-0611
44
ZNEO
®
CPU Core
User Manual
Returning From a Vectored Interrupt
If no interrupts are pending or the Chained Interrupt Enable Flag (CIRQE) is 0, executing
the Interrupt Return (IRET) instruction at the end of an interrupt service routine results in
the following operations:
1. Pop PC[31:24] from the stack.
2. Pop PC[23:16] from the stack.
3. Pop PC[15:8] from the stack.
4. Pop PC[7:0] from the stack.
5. Increment SP by 1 (so SP alignment is not changed).
Figure 11. Interrupt Vectoring Example
Memory
Interrupt Vector Quad
Interrupt
Vector
Table
Interrupt Service
Routine First
Vector[23:16] = 23H
Vector[15:8] = 45H
0023_4567H
0000_0014H
0000_0015H
Vector[7:0] = 67H
0000_0016H
0000_0017H
Vector[31:24] = 00H
Quad Base Address
Address
Instruction
Comentarios a estos manuales