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1. SIMPLE DELAY FUNCTION FOR 8051 IN C HOW TO
2. SIMPLE DELAY FUNCTION FOR 8051 IN C FULL
3. SIMPLE DELAY FUNCTION FOR 8051 IN C SOFTWARE

EA bit will enable the global interrupt.After that we make ET0 bit enabled which will enable the timer, if you dont set this pin HIGH then our timer will not work.On reload timer uploads the vlaue from TH0 into TL0 so thats why we have given the same value to TH0. TL0 has 0x05 in it which is the initial value of timer0 and it will count for 250 micro seconds.In mode 2, it will auto reload means once the timer0 overflows then it will comes back to its original value and will start again. In this function what I have done is I simply set the timer 0 to mode 2.In the above code, the main function is our InitTimer0 function.Void Timer0_ISR (void) interrupt 1 // It is called after every 250usec TMOD &= 0xF0 // Clear 4bit field for timer0 While(1) // Rest is done in Timer0 interrupt Sbit Out = P2^0 // Pin P2.0 is named as Out

SIMPLE DELAY FUNCTION FOR 8051 IN C SOFTWARE

SIMPLE DELAY FUNCTION FOR 8051 IN C FULL

TF0 is another register value, if its 1 then it means that our timer is full and if its 0 then it means our timer is still counting. Now when Timer0 will overflow then it will make TF0 bit HIGH. Now suppose I want my timer to start counting from 10 instead 0 then I will store 10 in my TL0 register and it will count from 10 instead 0 and when it reaches 255 it will overflow.

If we are talking about Timer0 then timer0 stores its value in TL0 register. In timers, there are few registers in which they store their value. Now when timer overflows, then it sends us a indication using which we generate our intterupt. Timers count from 0 to 255 in 8 bit mode as in 8 bit 255 is the maximum value and when timer hits the 255 number then we say that our timer is overflowed. so, now before gong into the details, let me first throw some light on how we are gonna implement this.

SIMPLE DELAY FUNCTION FOR 8051 IN C HOW TO

How to use Timer interrupt in 8051 Microcontroller ?Īs I explained earlier, we are gonna use Timer interrupt in 8051 Microcontroller. So, let's start with timers interrupt in 8051 Microcontroller and see how we are gonna do this. So, in this way after every two seconds the led will blink. For Timer interrupts, suppose I wanna blink my LED after every 2 seconds then what will I do is I will start a timer for 2 seconds and when this timer completes I will generate an interrupt.

Interrupt is kind of a background code which keeps on running in the background while the main code keeps on running in front but when the interrupt condition is fullfilled then it interrupts the main program and executes the functions defined in it. In programming codes there are many things which needs to run in background and appear when its time for them to appear. Now coming towards interrupt, interrupt is interrupt :P Yeah really, we call it interrupt because its an interrupt. So, these are different uses of a timer and clearly we can't neglect its importance, so today we are gonna see How to use these timer interrupt in 8051 Microcontroller.

You start the timer and then when it comes to 10 seconds then you can do your work. Timers are also used for delays like you wanna create some delay of 10 sec but you dont wanna use the delay function in your project so you can use timers. So, in short there are numerous uses of timers in a project. These timers are used for counting purposes like you want to start some countdown in your project then you can use these timers or you wanna create some clock then in that case as well you need timers. They normally have two timer in them named as Timer0 and Timer1. To generate delays within normal operation of the device with a delay duration of minutes to hours, a timer in conjunction with its interrupt and its service routine (ISR) should be utilized.Ī variable can act as a secondary counter to keep track of multiple timer overflows to generate the required delay range.Hello friends, hope you all are fine and having fun with your lives.In today's post, we are gonna see How to use timer interrupt in 8051 Microcontroller.8051 Microcontroller comes with timer as well. The delay routines offered by C compilers are typically write in assembler in a C callable routine as this is the only way to obtain any reasonable amount of precision of the duration regardless of compiler version. One of the few acceptable occasions to use a software generated delay is at system start up to allow peripherals to initialize properly, even then the delays should only be limited to the microsecond or millisecond range. Software generated delays also put the microcontroller in an unresponsive state, essentially locking it up for the duration of the delay.