1. Timers Chapter 10

2. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

3. Timers (cont.) Pulse Train Using Interrupts Measuring the Period of a Pulse Train Using Interrupts The Polaroid Ultrasonic Transducer –An Ultrasonic Tape Measure

5. Timer Counter

6. Timer System Control Register

7. Setting the timer count time

10. 68HC11 Timer Registers

13. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

17. Pulse Train Example

22. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

23. Input Capture

27. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

28. Pulse Accumulator

31. The 74C922 16-Key Encoder Connect pin 12 to PT7/PAI instead of PJ7

33. Pulse Accumulator on a 68HC11

36. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

37. Timing Interrupt Service Routines Traffic Lights Using Real-time Interrupt

38. Copy TRAFFIC.WHP to TRAFFIC2.WHP

39. Load TRAFFIC2.WHP TEST.SETUP TEST Add:

40. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

41. A Circular Queue empty Containing 2 values

45. Timers The 68HC12 Programmable Timer Output Compares Input Capture Pulse Accumulator Timing Interrupt Service Routines A Circular Queue Data Structure Keypad Interfacing Using Interrupts

48. Timers (cont.) Pulse Train Using Interrupts Measuring the Period of a Pulse Train Using Interrupts The Polaroid Ultrasonic Transducer –An Ultrasonic Tape Measure

49. Pulse Train

53. Timers (cont.) Pulse Train Using Interrupts Measuring the Period of a Pulse Train Using Interrupts The Polaroid Ultrasonic Transducer –An Ultrasonic Tape Measure

56. Timers (cont.) Pulse Train Using Interrupts Measuring the Period of a Pulse Train Using Interrupts The Polaroid Ultrasonic Transducer –An Ultrasonic Tape Measure

57. Polaroid Ultrasonic Ranging System

58. Waveforms of Ultrasonic Ranging System

62. Exercises