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Problem using UART0 in TM4C123 Tiva C Launch Pad

Embedded
I'm trying to interface UART0 with the my laptop using the ICDI  
the code I used :
 
```
#include <stdint.h>
#include "tm4c123gh6pm.h"
void UART0Tx(char c);
void delayMs(int n);
int main(void)
{
SYSCTL->RCGCUART |= 1; /* provide clock to UART0 */
SYSCTL->RCGCGPIO |= 1; /* enable clock to PORTA */
delayMs(20); /* wait for output line to stabilize */
/* UART0 initialization */
UART0->CTL = 0; /* disable UART0 */
UART0->IBRD =  104; /* 16MHz/16=1MHz, 1MHz/104=9600 baud rate */
UART0->FBRD =  11; /* fraction part, see Example 4-4 */
UART0->CC = 0; /* use system clock */
UART0->LCRH = 0x60; /* 8-bit, no parity, 1-stop bit, no FIFO */
UART0->CTL = 0x301; /* enable UART0, TXE, RXE */
/* UART0 TX0 and RX0 use PA0 and PA1. Set them up. */
GPIOA->DEN = 0x03; /* Make PA0 and PA1 as digital */
GPIOA->AFSEL = 0x03; /* Use PA0,PA1 alternate function */
GPIOA->PCTL = 0x11; /* configure PA0 and PA1 for UART */
delayMs(1); /* wait for output line to stabilize */
for(;;)
{
UART0Tx('M');
delayMs(1000) ; 
 
}
}
/* UART0 Transmit */
/* This function waits until the transmit buffer is available then */
/* writes the character in the transmit buffer. It does not wait */
/* for transmission to complete. */
void UART0Tx(char c)
{
while((UART0->FR & 0x20) != 0); /* wait until Tx buffer not full */
UART0->DR = c; /* before giving it another byte */
}
void delayMs(int n)
{
int i = 0 , j = 0 ; 
for(i = 0 ; i < n ; i++)
{
for(j = 0 ; j < 3180 ; j++)
{
 
}
}
}
```
and there are no problems with the COM port I've set it up in a correct way 
and All I get is this symbol 
[![enter image description here][1]][1]
 
 

Sourav Gupta

Permalink

There is a example code of uart_echo that can be found in the tivaware. Run that programme and check the connection once again to make sure that the code is ok. Check if it is working.

   Joined February 12, 2018      696
Monday at 02:11 PM