Review for Second Exam
- 1.
- Interrupts
- (a)
- Interrupt Vectors (and reset vector)
- (b)
- What happens to stack when you receive an enabled interrupt
- (c)
- What happens when you leave ISR with RTI instruction?
- (d)
- What setup do you need to do before enabling interrupts?
- (e)
- What do you need to do in interrupt service routine (clear source of
interrupt)?
- (f)
- How long (approximately) does it take to service an interrupt?
- 2.
- C Programming
- (a)
- Setting and clearing bits in registers
PORTA = PORTA | 0x02;
PORTA = PORTA & ~0x0C;
- (b)
- Using pointers to access specific memory location or port.
* (unsigned char *) 0x0400 = 0xaa;
#define PORTX (* (unsigned char *) 0x400)
PORTX = 0xaa;
- 3.
- Timer/Counter Related Subsystems
- (a)
- Real Time Interrupt
- (b)
- Pulse Width Modulation
- (c)
- Timer/PACTL
- i.
- Enable Timer
- ii.
- Timer Overflow Interrupt
- iii.
- Input Capture
- iv.
- Output Compare
- v.
- PWM with OC7 and OCx
- vi.
- Event count using PACTL
- vii.
- Gated time accumulation using PACTL
1999-03-25