[ARM] SPI interfacing using LPC2138

[Ravindrakant Jha]

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Code C - [expand]
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#include <LPC213X.H>
void delay(int msec)
{
    T0MCR=0X04;  //timer 0 match control register
    T0MR0=3000*msec;   //Timer 0 Match Register
    T0TC=0X00;        //Timer 0 timer counter
    T0TCR=0X01;      //Timer 0 timer control register
    while(T0TC<T0MR0);
                    }
 
void SPI_init() //initialization function
{  
  
   PINSEL0|=1<<8;   //SCK0 for SPI0 p0.5
   PINSEL0&=~(1<<9);
   PINSEL0|=1<<10; //MISO p0.5 Master i/p slave o/p
   PINSEL0&=~(1<<11); 
   PINSEL0|=1<<12;  //MOSI P0.6 Master o/p slave i/p
   PINSEL0&=~(1<<13);
   S0SPCCR = 64; 
   S0SPCR|=(1<<2)|(1<<3)|(1<<4)|(1<<5);//spi enable using microcontroller as master
                                       //spi sends and receive 8 bits of data
                                       //CPHA
                                       //CPOL
}
void SPI_tx(char data)   //SPI transmit function
{                  
  S0SPDR=data;//SPI data register
  while(!(S0SPSR&(0X80))); //SPIF low
}
char SPI_rx ()  //receive function
{
  while(!(S0SPSR&(0X80)));//SPI data receive 
  return(S0SPDR);
}
 void SPI_string(char *str)
 {
   while(*str!='\0')
   SPI_tx(*str);
 }
 
 
int main()
{
 
   IO0DIR |= (1<<7); //Port 0 direction register
    SPI_init();   // SPI initialization
   IO0CLR |= (1<<7); // slave select pin initially low
   SPI_string("Hello");
  while(1)
  {
    
    SPI_rx();
    delay(1);
  
  }
  //IO0SET |= (1<<7);
  
}

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In the above code data is received continuously with a constant value 48 in the SPI Debugger.
I just want to know where my code is lagging.