Random Characters in Terminal Emulator

Question

I am currently working on a project to select different outputs based on a text input from a laptop via USB.

What I am currently trying to do is send a character out from my PIC18F1320 to HyperTerminal, I have tried using variables but was recieveing rnadom characters such as smiley faces etc. I simplified my code to simply print a 1 however I am still recieving smily face symbols. I have checked that I am using the correct baud rate and there is definite communication between my laptop and the PIC, however at this point I am completely stuck as I have no idea why random characters are being output.

I have extremely little knowledge of C and any help would be appreciated

    #include <p18f1320.h>
    #include <usart.h>
    #include <stdio.h>
    #include <stdlib.h>

    void main()
    { 
        OSCCON = 0x70;  // 8MHz internal clock

        // Configure USART
        OpenUSART(  USART_TX_INT_OFF    &
                    USART_RX_INT_OFF    &
                    USART_ASYNCH_MODE   &
                    USART_EIGHT_BIT     &
                    USART_CONT_RX       &
                    USART_BRGH_LOW,
                    12);

        while (1)
        {
            putrsUSART("1");
        }
        CloseUSART();
    }

Answer 1

The internal RC oscillator on the PIC is not precise enough to run the USART at the desired speed - it can vary by ±2% from the expected frequency, which is probably far out enough to be causing the errors you're seeing. You will need to attach and configure an external crystal for correct results.

Answer 2

Put your data in RAM and send. See Harvard Architecture

char buf[10];
strcpy(buf, "Hello\n");  // This should cal special ROM to RAM strcpy();
putrsUSART(buf);

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Note: "I have checked that I am using the correct baud rate" may not be right. Until you received valid data, I would not be too confident about this.