R8C/20 Group, R8C/21 Group 12. Interrupts
Rev.2.00 Aug 27, 2008 Page 87 of 458
REJ09B0250-0200
12. Interrupts
12.1 Interrupt Overview
12.1.1 Types of Interrupts
Figure 12.1 shows the Interrupts.
Figure 12.1 Interrupts
• Maskable interrupt: The interrupt enable flag (I flag) enables or disables these interrupt. The
interrupt priority order can be changed based on the interrupt priority level.
• Non-maskable interrupt: The interrupt enable flag (I flag) does not enable or disable an interrupt. The
interrupt priority order based on interrupt priority level cannot be changed.
Interrupt
(non-maskable interrupt)
Hardware
Software
(non-maskable interrupt)
(maskable interrupt)
Special
Peripheral function
(1)
Undefined instruction (UND instruction)
Overflow (INTO instruction)
BRK instruction
INT instruction
Watchdog timer
Oscillation stop detection
Voltage monitor 2
Single step
(2)
Address break
(2)
Address match
NOTES:
1. Peripheral function interrupts in the MCU are used to generate the peripheral interrupt.
2. Do not use this interrupt. This is for use with development tools only.