receiving tons of dummy data from computer port

[einton]

Hi guys , i m involved in quite a annoying problem , the problem is when i tried to interface pic18f2580 to computer com port using program in mikroc pro i eventually received tons of dummy data without any break i dont know the problem but the data look like this

000013b0: 6B 7B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B k{kkkkkkkkkkkkkk
000013c0: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkkkkkkkkkkkkkk
000013d0: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkkkkkkkkkkkkkk
000013e0: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 7B 6B kkkkkkkkkkkkkk{k
000013f0: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkkkkkkkkkkkkkk
00001400: 6B 6B 7B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kk{kkkkkkkkkkkkk
00001410: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkkkkkkkkkkkkkk
00001420: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 7B 6B 6B 6B 6B kkkkkkkkkkk{kkkk
00001430: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkkkkkkkkkkkkkk
00001440: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkkkkkkkkkkkkkk
00001450: 6B 6B 6B 6B 7B 6B 6B 6B | 6B 6B 6B 6B 6B 6B 6B 6B kkkk{kkkkkkkkkkk
00001460: 6B 6B 6B 6B 6B 6B 6B 6B | 7B 6B 6B 6B 6B 6B 6B 6B kkkkkkkk{kkkkkkk
00001470: 6B 6B 6B 6B 6B 6B 6B 6B | 6B 6B 7B 6B 6B 6B 6B 6B kkkkkkkkkk{kkkkk
00001480: 6B 6B 6B 4B 5B 5B DB DB | DB DB DB DB DB DB DB DB kkkK[[ÛÛÛÛÛÛÛÛÛÛ
00001490: DB DB DB 6D DB DB D9 DB | DB 9B 9B BB B3 B3 B3 B3 ÛÛÛmÛÛÙÛÛ››»³³³³
000014a0: B3 B3 B7 F7 ³³·÷

i m using the advanced port terminal i have also used mikroc pro usart tool but the same tons of data i eventually receive when i plug on , my program follows as

char uart_rd;

void main() {

  ADCON1 |= 0x0F;                 // Configure AN pins as digital

  UART1_Init(9600);               // Initialize UART module at 9600 bps
  Delay_ms(1000);                  // Wait for UART module to stabilize


  while (1) {
  

   if (UART1_Data_Ready()) {      // If data is received,
     uart_rd = UART1_Read();      //   read the received data,
     UART1_Write(uart_rd);

    }
  }
 }

i dont know what the possible reason could be i haev checked the board and i think all connections are fine , please tell any thing if u could suggest.

 

[Pommie]

Do you have a MAX232 (or equivalent) in your circuit?

Mike.

 

[Mr RB]

6B = 01101011
DB = 11011011

All your data is alternating between 1 and 0, I think you might have the wrong baudrate selected somewhere.

 

[Noggin]

I'd be more concerned if there was anything but 1's and 0's.

 

[Pommie]

The fact that data is received when none is being sent suggests the wrong polarity. Or, the OP has both ends set to echo received data.

Mike.