MC68HC705P6A Datasheet, PDF (45/130 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Advance Information — MC68HC705P6A
Section 5. Interrupts
5.1 Contents
5.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
5.3 Interrupt Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.3.1 Reset Interrupt Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3.2 Software Interrupt (SWI). . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3.3 Hardware Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3.3.1 External Interrupt (IRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.3.3.2 Input Capture Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.3.3.3 Output Compare Interrupt . . . . . . . . . . . . . . . . . . . . . . . .49
5.3.3.4 Timer Overflow Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.2 Introduction
The MCU can be interrupted six different ways:
1. Non-maskable software interrupt instruction (SWI)
2. External asynchronous interrupt (IRQ)
3. Input capture interrupt (TIMER)
4. Output compare interrupt (TIMER)
5. Timer overflow interrupt (TIMER)
6. Port A interrupt (if selected via mask option register)
Interrupts cause the processor to save the register contents on the stack
and to set the interrupt mask (I bit) to prevent additional interrupts. Unlike
reset, hardware interrupts do not cause the current instruction execution
to be halted, but are considered pending until the current instruction is
completed.
MC68HC705P6A — Rev. 2.0
MOTOROLA
Interrupts
Advance Information
45