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Table of Contents
ii
7751 Group User’s Manual
CHAPTER 4. INTERRUPTS
4.1 Overview ..................................................................................................................................4-2
4.2 Interrupt sources................................................................................................................... 4-4
4.3 Interrupt control .................................................................................................................... 4-6
4.3.1 Interrupt disable flag (I) ................................................................................................ 4-8
4.3.2 Interrupt request bit....................................................................................................... 4-8
4.3.3 Interrupt priority level select bits and processor interrupt priority level (IPL) .......4-8
4.4 Interrupt priority level........................................................................................................ 4-10
4.5 Interrupt priority level detection circuit ........................................................................ 4-11
4.6 Interrupt priority level detection time ............................................................................ 4-13
4.7
Sequence from acceptance of interrupt request to execution of interrupt routine ...........................
4-14
4.7.1 Change in IPL at acceptance of interrupt request..................................................4-16
4.7.2 Storing registers........................................................................................................... 4-17
4.8 Return from interrupt routine........................................................................................... 4-18
4.9 Multiple interrupts............................................................................................................... 4-18
4.10 External interrupts (INT
i
interrupt)................................................................................ 4-20
4.10.1 Function of INT
i
interrupt request bit ...................................................................... 4-23
4.10.2 Switch of occurrence factor of INT
i
interrupt request...........................................4-25
CHAPTER 5. TIMER A
5.1 Overview ..................................................................................................................................5-2
5.2 Block description .................................................................................................................. 5-3
5.2.1 Counter and reload register (timer Ai register) ......................................................... 5-4
5.2.2 Count start register........................................................................................................ 5-5
5.2.3 Timer Ai mode register ................................................................................................. 5-6
5.2.4 Timer Ai interrupt control register ............................................................................... 5-7
5.2.5 Port P5 and port P6 direction registers ..................................................................... 5-8
5.3 Timer mode ............................................................................................................................ 5-9
5.3.1 Setting for timer mode ................................................................................................ 5-11
5.3.2 Count source ................................................................................................................ 5-13
5.3.3 Operation in timer mode............................................................................................. 5-14
5.3.4 Select function ............................................................................................................. 5-15
5.4 Event counter mode ........................................................................................................... 5-19
5.4.1 Setting for event counter mode ................................................................................. 5-22
5.4.2 Operation in event counter mode.............................................................................. 5-24
5.4.3 Select functions............................................................................................................ 5-26
5.5 One-shot pulse mode......................................................................................................... 5-30
5.5.1 Setting for one-shot pulse mode ............................................................................... 5-32
5.5.2 Count source ................................................................................................................ 5-34
5.5.3 Trigger........................................................................................................................... 5-35
5.5.4 Operation in one-shot pulse mode ............................................................................ 5-36
5.6 Pulse width modulation (PWM) mode ............................................................................ 5-39
5.6.1 Setting for PWM mode ............................................................................................... 5-41
5.6.2 Count source ................................................................................................................ 5-43
5.6.3 Trigger........................................................................................................................... 5-43
5.6.4 Operation in PWM mode ............................................................................................ 5-44