Panasonic MN101C77C - Manual (Page 101)

III - 7
Chapter 3 Interrupts
Overview
■ Interrupt Level and Priority
This LSI allocated vector numbers and interrupt control registers (except reset interrupt) to each inter-
rupt. The interrupt level (except reset interrupt, non-maskable interrupt) can be set by software, per each
interrupt group. There are three hierarchical interrupt levels. If multiple interrupts have the same priority,
the one with the lowest vector number takes priority. For example, if a vector 3 set to level 1 and a vector
4 set to level 2 request interrupts simultaneously, vector 3 interrupt will be accepted.
Level 1
Level 2
Vector 1 (Non-maskable interrupt)
Level 0
Vector 3
Vectors 2, 5, 6
Vectors 4, 8
Priority
1
2
3
4
5
6
7
Vector 1
Vector 2
Vector 5
Vector 6
Vector 3
Vector 4
Vector 8
Interrupt level
setting range
Interrupt vector No.
Figure 3-1-3 Interrupt Priority Outline