Suppose you are writing your own high levels functions to read and write the digital pins. a. Write 9 "#define" macros for PINB, C,D, PORTB, C,D and DDRB, C,D, so that you can use them in part b. b. Write the C code to set up the PIN, PORT, and DDR registers for the following functions. Be sure to consider all possible input cases, ranges, etc. WriteGPIOhigh(int port, unsigned char mask) //port=0 means PORTB, 1=PORTC, 2=PORTD //mask = 8 bit mask indicating which pins to write high. Ex. 0001 0010= Write bit 1 and 4 high WriteGPIOlow(int port, unsigned char mask) //port=0 means PORTB, 1=PORTC, 2=PORTD //mask = 8 bit mask indicating which pins to write low. Ex. 0010 0001= Write bit 0 and 5 low EnableGPIOpullup(int port, unsigned char mask) //port=0 means PORTB, 1=PORTC, 2=PORTD //mask = 8 bit mask indicating which pins to enable pullup. unsigned char readGPIOport(int port) //port=0 means PORTB, 1=PORTC, 2=PORTD //returns all 8 pins from port "port" by way of an unsigned char Are the above functions sufficient to completely implement GPIO functionality? If not propose modifications or additions necessary to completely implement full GPIO functionality.