This program is the example of MC80F0448 functions like Timer, LED Driving , Buzzer Driving etc. The Digital Clock & Stop Watch is operated by Timer 4 and Watch Timer. And this has one Buzzer for Alarm and four keys; Hour, Minute, Reset and Mode.
The buzzer turns on during 500ms every second for 2 minutes, if clock time equals alarm time. Time is displayed by four 7-segments LED.
1. Timer 4
• 16 bits, fxin = 4Mhz, Interrupt Cycle = 1 sec
2. Watch Timer
• fxin = 4Mhz, Interrupt Cycle = fxin / 8192 = 2ms
• Output frequency = 1.059Khz
• Operation: 500ms On / 500ms Off per 1 second
4. Circuit Diagram
Source: ABOV Semiconductor