Programming Embedded Systems, 2nd Edition

Working with Serial Ports

We looked at a serial driver in Chapter 7. The Monitor and Control program uses the same serial driver with some additional functionality.

One change to the serial driver is the addition of a “put string” function, serialPutStr. This function, which follows, allows strings to be sent out the serial port through a single call rather than having to specify each character in order. This is similar to the standard C printf function, which calls the serialPutChar function repeatedly until the entire string has been transmitted out the serial port.

/**********************************************************************
 * 
 * Function:    serialPutStr
 *
 * Description: Outputs a string to the serial port.
 *
 * Notes:       
 *
 * Returns:     None.
 *
 **********************************************************************/
void serialPutStr(char const *pOutputStr)
{
    char const *pChar;

    /* Send each character of the string. */
    for (pChar = pOutputStr; *pChar != '\\0'; pChar++)
        serialPutChar(*pChar);
}