EMBEDDED SYSTEM C CODE (we need the source code)

Suppose that we would like to design the following system by using, PIC16F877, 4-digit 7-segment display Phone keypad. Show appropriate connections (if you want you can use any interrupt). Then, (i) Write a function/subroutine for the required initializations. (ii) Write a function/subroutine to display 2-digit integer to the middle of the displays where the 2-digit integer is the argument of the function.; Write a function/subroutine for the keypad that scans the keypad and returns to an integer number (or 20 if '*' or '#' is pressed); (vi) By using the functions, which you wrote, write a main function for the following tasks: At the beginning display two invalid characters "" on the second and third seven segment displays. The first numerical value should be written to the second display from the right and second numerical digit to the third display from the right. The two decimal numbers (Number N) should be displayed for 30 s. On the displays and then it should count down from N to o seven times (each count should be completed in 1 minute). Then it should be return to the beginning and wait till a new N