Hello.
So in this final section we are going to talk about how to create interrupt without timers.
So I should point out we are creating an entirely new cookbook series for interrupt on the call text.
And with that cookbook series we are going to give a detailed explanation tutorial for interrupt to
what we are going to do here and this cause is a very very short summary of interrupt.
What time is I don't by any means expect you two to understand the intricacies of interrupt from this
lesson but it's just a short course a short tutorial to show you how to create timer interrupt.
So before we start I'll just give you an overview of interrupts for people who don't know what interrupt.
So over here we have a picture of a person waiting for the phone to ring.
Right.
Interrupt versus pull in so a single microprocessor can save several devices.
As we know that and yet two ways to do that.
You can use interrupt or you can use pull in in the interrupt method whenever any a device needs a service
that device notifies the CPA you by sending it an interrupt signal upon receiving an interrupt signal
to see you interrupt whatever it is doing says the device the program associated with it interrupt is
called the interrupt service routine or the interrupt handler in Poland.
The CPSU continuously monitors the stages of a given device when the status condition is met.
It performs the service.
After that it moves on to monitor the next device until each one is serviced.
So look at this bunch here waiting for the phone to ring.
You can take this man as the CPSU right.
How do we operate in our daily lives.
We go about our lives read a book watch a movie or do whatever you doing when the phone rings.
Then you pick up the phone to ring tone of the phone is the interrupt signal.
Right.
But in this picture we have a person sitting and waiting for the phone.
A person looking at a phone to ring.
This is Poland right.
This man is practically pulling the phone to ring rather than going about his daily life.
Wait until he had to rent one and then pick up the phone.
Right.
So that is the difference between interrupt and pull in and which polling a lot of CPSU is wasted because
the CPE would always have to check and monitor the status of a given device.
And if you have many devices the CBI has to monitor each and every one of them and see what the condition
is met or not met whereas Yeah the resources that particular CPE resources could be put to better use.
So this is where interrupt comes in.
And often we implement polling by using if statement like if a is less than beat and do this if it is
greater than this if pin B is high or if this or if that's often performed poorly in this way.
So we'll go ahead and go to you vision and write our interrupt program and create to interrupt service
routines and let the let the program run automatically whenever they interrupt Cass.