File content as of revision 29:dead10cce6e9:

//these are defines for the messages that are sent from the PC across the USB
//these messages produce reactions on the mbed
const unsigned char  FIRE_TRIGGER_MSG   = 1;

const unsigned short serBuffMax = 18;
char serBuf[serBuffMax];
int serBufChars=0;

//flags to control the PC command actions
bool fireTrigger    =false;

unsigned char CR = 0x0d;                //ASCII Carriage Return
unsigned char LF = 0x0a;                //ASCII Line Feed

bool validMessage = false;


void readFromPC()
{
    //  should this be a while rather than if ??? -- may have multiple bytes in buffer
    if (toPC.readable()) //read a PC serial byte and test it for a command
    {
        // Read in next character
        // why not read all available bytes
        unsigned char inChar = 0;
        inChar = toPC.getc();  //read char from the USB serial link to the PC
        
        //incoming messages will end witb a CR / LF -- disregard these chars
        if (inChar == CR || inChar == LF)  return; //CR is a 0x0a
        
        //all incoming messages will start with "mbedMessage", "messageType", numberDataBytes, and will end with CR & LF
        //1) look for the mbedMessage and then get the next byte as numberDataBytes;
        //2) read the next numberDataBytes and then look for CR & LF
        //if 1) & 2)  are successful, declare a valid incoming message
        //if message is valid, then send a response as a repeat of the original message
        //
        
    }  //end pc.readable
};