M30222 Datasheet, PDF (37/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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Specifications in this manual are tentative and subject to change
MITSUBISHI MICROCOMPUTERS
M30222 Group
Rev. G
Overview of Interrupts
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Interrupts and Interrupt Vector Tables
If an interrupt request is accepted, program execution branches to the interrupt routine set in the
interrupt vector table. Set the first address of the interrupt routine in each vector table. Figure 1.22
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
Vector address + 0
Vector address + 1
Low address
Mid address
LSB
Vector address + 2
0000
High address
Vector address + 3
0000
0000
Figure 1.22. 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 1.17 shows the interrupts assigned to the fixed vector tables and
addresses of vector tables.
Table 1.17. Interrupts assigned to the fixed vector tables and addresses of vector tables
Interrupt source
Undefined instruction
Overflow
BRK instruction
Vector table addresses
Address (L) to address (H)
FFFDC16 to FFFDF16
FFFE016 to FFFE316
FFFE416 to FFFE716
Address match
Single step (Note)
Watchdog timer
FFFE816 to FFFEB16
FFFEC16 to FFFEF16
FFFF016 to FFFF316
DBC (Note)
NMI
Reset
FFFF416 to FFFF716
FFFF816 to FFFFB16
FFFFC 16 to FFFFF16
Note: Interrupts used for debugging purposes only.
Remarks
Interrupt on UND instruction
Interrupt on overflow
If thisvector contains FFFFF16, program execution starts from
the address shown by the vector in the variable vector table
Requires address-matching interrupt enable bit
Do not use
Do not use
External interrupt by input to NMI pin
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