#include <stdint.h>
#include <stdbool.h>
#include "tm4c123gh6pm.h"


void UART7_init(void);
void UART7_write(char data);
char UART7_read(void);
void PortE_init(void);
void LED_Control(char);


int main(void)
{
    char recievedchar;

    UART7_init(); // UART 7 Initialization
    PortE_Init(); // PORT E Initialization

    while(1)
        {
        recievedchar = UART7_read(); // Read a character from the UART

        UART0_Write(receivedChar); // Give the character back to UART

        LED_Control(receivedChar); // LED Control based on UART input
        }

}


void UART7_init(void)
    {
    SYSCTL_RCGCUART_R |= 0x80;   // Enable clock to UART7
    SYSCTL_RCGCGPIO_R |= 0x10  // Enable clock to Port E for UART7

    // UART7 TX/RX on PE1/PE0
    GPIO_PORTE_AFSEL_R |= 0x03;  // Enable alt function on PE0, PE1
    GPIO_PORTE_DEN_R |= 0x03;    // Enable digital on PE0, PE1
    GPIO_PORTE_PCTL_R |= 0x11;   // Configure PE0 and PE1 for UART
    GPIO_PORTE_AMSEL_R &= ~0x03; // Disable analog on PE0, PE1


    // UART7 initialization
    UART0_CTL_R &= ~0x01;        // Disable UART0
    UART0_IBRD_R = 104;          // Baud rate = 9600, Integer Baud Rate Divisor
    UART0_FBRD_R = 11;           // Fractional Baud Rate Divisor
    UART0_LCRH_R = 0x70;         // 8-bit, no parity, 1-stop bit, enable FIFOs
    UART0_CTL_R |= 0x301;        // Enable UART0, TX, RX

    }

char UART0_Read(void)
    {

    while((UART0_FR_R & 0x10) != 0); // Wait until RXFE is 0 (receive FIFO not empty)
    return UART0_DR_R & 0xFF;        // Read the received character

    }

void UART0_Write(char data)
    {

    while((UART0_FR_R & 0x20) != 0); // Wait until TXFF is 0 (transmit FIFO not full)
    UART0_DR_R = data;               // Transmit the data

    }


void PortF_Init(void)
    {

    SYSCTL_RCGCGPIO_R |= 0x20;       // Enable clock to Port F
    GPIO_PORTF_LOCK_R = 0x4C4F434B;  // Unlock Port F for commit
    GPIO_PORTF_CR_R |= 0x0E;         // Allow changes to PF1, PF2, PF3 (RGB LEDs)
    GPIO_PORTF_DIR_R |= 0x0E;        // Set PF1, PF2, PF3 as outputs
    GPIO_PORTF_DEN_R |= 0x0E;        // Enable digital on PF1, PF2, PF3

    }

void LED_Control(char receivedChar)
    {

        switch(receivedChar)
            {
                case 'R':
                    GPIO_PORTF_DATA_R = 0x02;  // Turn on RED LED (PF1)
                    break;
                case 'B':
                    GPIO_PORTF_DATA_R = 0x04;  // Turn on BLUE LED (PF2)
                    break;
                case 'G':
                    GPIO_PORTF_DATA_R = 0x08;  // Turn on GREEN LED (PF3)
                    break;
                default:
                    GPIO_PORTF_DATA_R = 0x00;  // Turn off all LEDs
                    break;
            }
    }