M16C62N Datasheet, PDF (40/213 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Interrupt
Mitsubishi microcomputers
M16C / 62N Group (80-pin)
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Interrupts and Interrupt Vector Tables
If an interrupt request is accepted, a program branches to the interrupt routine set in the interrupt vector
table. Set the first address of the interrupt routine in each vector table. Figure 1.10.2 shows the format for
specifying the address.
Two types of interrupt vector tables are available — fixed vector table in which addresses are fixed and
variable vector table in which addresses can be varied by the setting.
MSB
LSB
Vector address + 0
Low address
Vector address + 1
Mid address
Vector address + 2
Vector address + 3
0000
0000
High address
0000
Figure 1.10.2. Format for specifying interrupt vector addresses
• Fixed vector tables
The fixed vector table is a table in which addresses are fixed. The vector tables are located in an area
extending from FFFDC16 to FFFFF16. One vector table comprises four bytes. Set the first address of
interrupt routine in each vector table. Table 1.10.1 shows the interrupts assigned to the fixed vector
tables and addresses of vector tables.
Table 1.10.1. Interrupts assigned to the fixed vector tables and addresses of vector tables
Interrupt source Vector table addresses
Remarks
Address (L) to address (H)
Undefined instruction FFFDC16 to FFFDF16 Interrupt on UND instruction
Overflow
FFFE016 to FFFE316 Interrupt on INTO instruction
BRK instruction
FFFE416 to FFFE716 If the vector contains FF16, program execution starts from
the address shown by the vector in the variable vector table
Address match
FFFE816 to FFFEB16 There is an address-matching interrupt enable bit
Single step (Note)
FFFEC16 to FFFEF16 Do not use
Watchdog timer
________
DBC (Note)
NMI
FFFF016 to FFFF316
FFFF416 to FFFF716
FFFF816 to FFFFB16
Do not use
_______
External interrupt by input to NMI pin
Reset
FFFFC16 to FFFFF16
Note: Interrupts used for debugging purposes only.
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