7-sement digit display using Keypad.

Yes i knew, I just want to look at main program starting from void main, to scan keyboard and do something and keep on monitoring.

Just like

Keypad Routine // I have to scan key that too have to try with main.
Main Program // ?? I doesnt have and i have no idea also.

Thats wat asked very simple code to get an idea to scan keyboard and make atleast Led to ON.

You already have simple routine for scanning keyboard. All you need to do is write simple code to decide what to do if a key isn't pressed, or what to do, depending on the number of the pressed key.

If you do not know any C at all, then you should first learn a bit of C, before trying to write embedded applications.

At your school, you should already have received the information you need. If not, then talk with your teacher.

Just remember that copy-paste of code you find on the net can be dangerous. Your teacher may also have seen the very same code. Or your posts here.

Thanks Per Westermark,
This is not for any school purpose, I am electronic hobbiest.
Even i myself completed Basic LCD application using the routiens, I can able to understand the coding with simple example by initializing it then displaying something by calling data function.

But in keyboard i have the routine, but if i have basic code which one to call first and which will return the key value to me kinda simple 4 line code to scan the single key is enough for me to understand the concepts. I have seen many keypad application but all mingle with LCD, So getting confused, Thats wat asked for displaying digit using 7-segment. Really it will save my time as well as make me to understand the concept stronger.

But the code you already have has one function that must called before you may use the other function. Always initialization functions first.

And it has one function that will return a number between 0 and 16, where 0 means no key was pressed.

All you have to do is call the init function. Then in a loop call the get-key function and assign the result to a variable.

Then use a switch statement or a number of if statements to decide what to do for the 17 different results you may get from the keyboard function.

If you still do not know what to do, you will just have to start by getting a book about the C language. It really is important that you read up on the language before you try to use real hardware. You will not get a working program unless you understand what different code lines does, and until you have a basic understanding of the available building blocks and how they can be combined to from a program.

Thanks for your nice information,
As u mentioned, i am little weak in C concepts, But understanding easily through practical applications than theory books. I mean the lines, what is it actually doing and all. Anyhow will write a code as u said and will try. Since i am week in C only asked that 4 line codes from others. Once i get the basics, i will expand it to complex applications. Will try it soon.
Thanks.

Does the below program make Port 1 high when keypad given the value 5 as output and Port 1 as low if key value is 6?

void main(){
keypad_init();
while (1){
get_key(key);
if (key == 5)
{ P1=1;
} if (key == 6)
{ P1=0;
} }
}

Above code works with the given routine?.
Since i have no access to kiel right now, i am simply asking this now.
Its just my rough code, Please help me if any mistakes.
Thanks

The function get_key() does not take any parameter. It returns a value, so you call it with key=get_key().

Thanks a lot. this is where my actual doubt is.

So,
while (1){
key = get_key();
If(key == 5){
P1 = 1;
} If(key == 6){
P1=0;
} }

So it will keep monitoring key value from get_key() and will assign to local variable key, if 5 P1 -> high,
If 6 P1->low.

Will try the routine and this code with keil.

Hi Per Westermark,
Thanks for your help, It is working fine.
Will give the remaining code since it will helpful to other peoples like me,
The remaining code for the above routine is,

void main(){
unsigned int key;
key_init();
while (1){
key = get_key();
If(key == 5){
P1 = 0xFF;
}
If(key == 6){
P1=0;
}
}
}

Where the above works fine which will simply make P1 as high if key value is 5 and low if 6. For remaining keys it will latch the previous value.

It is often better to use space instead of tab for indenting the code. With spaces, the indent will be consistent when switching between editors or when presenting the code on the net.

Another thing. For an 8-bit processor, the code will be smaller and faster if you use 8-bit variables whenever you can, instead of using the 16-bit int data type.

Don't retype source code when making posts. Always copy/paste, to make sure you don't introduce errors. In C, the keyword is "if", and not "If".

In C, a function that doesn't take parameters should be specified with "void" instead of an empty list between the parentheses.

int main(void){
    unsigned char key;

    key_init();
    while (1) {
        key = get_key();
        if (key == 5) {
            P1 = 0xFF;
        }
        if (key == 6) {
            P1 = 0;
        }
    }
    return 0;
}

I would simply recommend that you always use spaces for indenting code - never use TABs!

The interpretation of TABs is entirely undefined - even different users of the same application may see different results due to different user settings!

The only thing you can be certain of with TABs is that they will not give reliable results!

Thanks for your kind guidance,
Since i am in learning phase, i am making many mistakes. Will try to rectify it through experience.

I made the program as u said, It was working great.
So i got excited, Your coding style is really good, Will follow it in future.

Thanks.