Variable Vector Table - Renesas R8C/Tiny Series Software Manual

Chapter 1 Overview

1.10.2 Variable Vector Table

The variable vector table is an address-variable vector table. Specifically, this 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.
The variable vector table is comprised of four bytes per table. Each vector table must contain the
interrupt handler routine's entry address.
Each vector table has software interrupt numbers (0 to 63). The INT instruction uses these software
interrupt numbers.
Interrupts from the peripheral functions built in each M16C model are allocated to software interrupt
numbers 0 through 31.
b19
INTB IntBase
IntBase+4
IntBase+8
IntBase+252
Figure 1.10.2 Variable vector table
b0
20
1.10 Vector Table


0




1
 
Vectors accommodat-


ing peripheral I/O


interrupts






31

Software interrupt

32

numbers
33







63