Uploaded October 2012 | Updated September 2026, 2 weeks ago
In this example we have configured 8051 timer0 for time calculation. There are 4 different modes for timer0 in 8051. We have selected 8 bit auto reload mode. In this mode timer0 hardware is automatically reset upon overflow to a predefined value and again starts counting up. Timer0 counts up 1 after 12 clocks of main system clock oscillator. So if we are using 12 MHz crystal then timer0 input frequency will be 1 MHz.
Here in this project system clock is of 24 MHz and timer0 input clock is 2 MHz. It is reset to value 6 after each overflow. Simply each timer interrupt is occurred after 125 micro seconds. And so in this way if 8 interrupts has occurred then 1 millisecond has passed and if 8000 interrupts has occurred then 1 second has passed and so on. In this way we calculate hours and minutes also. This time is updated on 16×2 LCD regularly. For detail of LCD interfacing please see 8051 To 16×2 LCD Interfaing. Buttons are provided for time settings.
Our Blog :- electronicswork.wordpress.com
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Please watch: "Lifi Communication by Arduino UNO Download Project"
youtube.com/watch?v=c4gC8dbaiZg
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In this example we have configured 8051 timer0 for time calculation. There are 4 different modes for timer0 in 8051. We have selected 8 bit auto reload mode. In this mode timer0 hardware is automatically reset upon overflow to a predefined value and again starts counting up. Timer0 counts up 1 after 12 clocks of main system clock oscillator. So if we are using 12 MHz crystal then timer0 input frequency will be 1 MHz.
Here in this project system clock is of 24 MHz and timer0 input clock is 2 MHz. It is reset to value 6 after each overflow. Simply each timer interrupt is occurred after 125 micro seconds. And so in this way if 8 interrupts has occurred then 1 millisecond has passed and if 8000 interrupts has occurred then 1 second has passed and so on. In this way we calculate hours and minutes also. This time is updated on 16×2 LCD regularly. For detail of LCD interfacing please see 8051 To 16×2 LCD Interfaing. Buttons are provided for time settings.
Our Blog :- electronicswork.wordpress.com
-~-~~-~~~-~~-~-
Please watch: "Lifi Communication by Arduino UNO Download Project"
youtube.com/watch?v=c4gC8dbaiZg
-~-~~-~~~-~~-~-
