#include

#include "../inc/tm4c123gh6pm.h"

unsigned long In; // input from PF4 unsigned long Out; // output to PF2 (blue LED) // Function Prototypes void PortF_Init(void); // 3. Subroutines Section // MAIN: Mandatory for a C Program to be executable int main(void){ // initialize PF0 and PF4 and make them inputs PortF_Init(); // make PF3-1 out (PF3-1 built-in LEDs) while(1){ In = GPIO_PORTF_DATA_R&0x10; // read PF4 into Sw1 In = In>>2; // shift into position PF2 Out = GPIO_PORTF_DATA_R; Out = Out&0xFB; Out = Out|In; GPIO_PORTF_DATA_R = Out; // output } } // Subroutine to initialize port F pins for input and output // PF4 is input SW1 and PF2 is output Blue LED // Inputs: None // Outputs: None // Notes: ... void PortF_Init(void){ volatile unsigned long delay; SYSCTL_RCGC2_R |= 0x00000020; // 1) activate clock for Port F delay = SYSCTL_RCGC2_R; // allow time for clock to start GPIO_PORTF_LOCK_R = 0x4C4F434B; // 2) unlock GPIO Port F GPIO_PORTF_CR_R = 0x1F; // allow changes to PF4-0 // only PF0 needs to be unlocked, other bits can't be locked GPIO_PORTF_AMSEL_R = 0x00; // 3) disable analog on PF GPIO_PORTF_PCTL_R = 0x00000000; // 4) PCTL GPIO on PF4-0 GPIO_PORTF_DIR_R = 0x0E; // 5) PF4,PF0 in, PF3-1 out GPIO_PORTF_AFSEL_R = 0x00; // 6) disable alt funct on PF7-0 GPIO_PORTF_PUR_R = 0x11; // enable pull-up on PF0 and PF4 GPIO_PORTF_DEN_R = 0x1F; // 7) enable digital I/O on PF4-0 }

Modify the code so that it flashes the red LED to send the Morse code for SOS continuously. That is three short flashes followed by three long flashes followed by three short flashes and then a pause. You will need to write a wait function for timing. This can be a simple for loop that just counts. Turn in a short write up with your C code and a short video of the LED sending SOS.