SPI communication protocol stellaris launchpad/

Howdy, 

I have a half duplex spi device that i am setting up my spi protocol to run on my stellaris using the ssi library. I need to set it up so that the stellaris does not read during transmission of data to the device.

the protocol is like this

The code i Wrote for write is as follows. Mind the conversion from char to long for data put then back to char from long

int readfromspi_serial
(
    unsigned short       headerLength,
    const unsigned char *headerBuffer,
    unsigned long        readlength,
    unsigned char       *readBuffer
)
{
    int i=0;
    unsigned char x2;
    unsigned long y1;

    //Enable The Slave Select pin for this device
    GPIO_PORTF_DATA_R &= ~(0x04);

	for(i=0; i<headerLength; i++)
	{
		
		y1 = *(headerBuffer + i);
		SSIDataPut(SSI0_BASE, y1);
		while(SSIBusy(SSI0_BASE))
		{
		}
		//need to make sure to ignore reads during this time
	}

	for(i=0; i<readlength; i++)
	{
	    x2 = *(readBuffer + i);
	    y1 = (long) x2;

      //SSIDataGet(unsigned long ulBase, unsigned long *pulData)
	   SSIDataGet(SSI0_BASE, &y1);
	   while(SSIBusy(SSI0_BASE))
	   {
	   }
	   x2 = (char) y1;
	   *(readBuffer + i) = x2;
        }

	//Disable slave select pin
	GPIO_PORTF_DATA_R |= 0x04;



    return 0;
} // end readfromspi()

Thanks for any help!