Variable Vector Tables - Renesas R8C/Tiny Series Software Manual

Chapter 1 Overview

1.10.2 Variable Vector Tables

A variable vector table is an address-variable vector table. Specifically, this type of vector table is a 256-
byte interrupt vector table that uses the value indicated by the interrupt table register (INTB) as the entry
address (IntBase). Figure 1.10.2 shows a variable vector table.
Variable vector tables are composed of four bytes per table. Each vector table must contain the inter-
rupt handler routine's entry address.
Each vector table has software interrupt numbers (0 to 63), which are used by the INT instruction.
Interrupts for the on-chip peripheral functions of each M16C model are allocated to software interrupt
numbers 0 through 31.
b19
INTB IntBase
Figure 1.10.2 Variable Vector Table
Rev.2.00 Oct 17, 2005
REJ09B0001-0200
b0
IntBase+4
IntBase+8
IntBase+252
page 20 of 263
1.10 Vector Tables


0


 
1


Vectors accommodat-


ing peripheral I/O


interrupts




 
31

Software interrupt

32

numbers
33







63