#include "sfr_r813.h"



#pragma interrupt Timer_X_int;			// Eingetragen als Vector 22
#pragma interrupt serial_receive_int;		// Eingetragen als Vector 20

int counter = 0;

void send_serial_1(unsigned char data);
unsigned char receive_serial_1 (void);
void UART1_init(void);
void status_led(void);




void main(void)
{

    /*-------------------------------------------------
    -  Change on-chip oscillator clock to Main clock  -
    -------------------------------------------------*/

    prc0 = 1;           			/* Protect off */
    cm13 = 1;           			/* Xin Xout */
    cm15 = 1;           			/* XCIN-XCOUT drive capacity select bit : HIGH */
    cm05 = 0;           			/* Xin on */
    cm16 = 0;           			/* Main clock = No division mode */
    cm17 = 0;
    cm06 = 0;           			/* CM16 and CM17 enable */
    asm("nop");         			/* Waiting for stable of oscillation */
    asm("nop");
    asm("nop");
    asm("nop");
    ocd2 = 0;           			/* Main clock change */
    prc0 = 0;           			/* Protect on */

    asm( "\tFSET	I");			/* Enable interrupt */

    /*-------------------------------------------------
    -  Setting main cycle timer                       -
    -  20 MHz * 1/32 * 1/250 * 1/250 => 10 Hz         -
    -------------------------------------------------*/
    
    txmr 	= 0x00;				/* Timer mode for Timer X */
    prex 	= 250-1;			/* Set Prescaler X register to 250 */
    tx   	= 250-1;			/* Set Timer X register to 250*/				 
    txck0	= 0;				/* Timer Count source = f32 */
    txck1	= 1;
    txic	= 0x04;				/* Timer interrupt priority level = 4 */
    s1ric	= 0x07;				/* UART1 Receive interrupt priority level = 7 */
    s1tic	= 0x06;				/* UART1 Transmit interrupt priority level = 7 */
    txs		= 1;				/* Timer X count start flag -> start */
    pd1		= 0x0F;				/* Set Port 1.0 - 1.3 be used for output*/
    p1		= 0x00;				/* Set Port 1.0 - 1.3 to High */
	
    UART1_init();


    while (1)
    {
	
    };

}




/**********************************
***  Timer X interrupt routine  ***
**********************************/

void Timer_X_int(void)				// Funktioniert ohne Probleme alle 0,5 Sekunden
{
	if(counter >= 5)
	{
		counter = 0;
		status_led();			
	}
		
	counter++;	
}

/**********************************
***  UART1 interrupt routine  ***
**********************************/

void serial_receive_int(void)			// Wird nur einmal ausgeführt !!!!!!
{	
	send_serial_1('O');			
	send_serial_1('K');	
}

/**********************************
***  Status LED  ******************
**********************************/

void status_led(void)
{
	if(p1 == 0x00)
	{
		p1 = 0x08;			// Wenn LED aus war, schalte die LED an
	}
	else
	{
		p1 = 0x00;			// Sonst, schalte die LED aus
	}
}


/**********************************
***  UART1 Senderoutine  **********
**********************************/

void send_serial_1(unsigned char data)
{
	while (ti_u1c1 == 0);	        	// Wait for transmission buffer emty
	u1tb = data;       	        	// Set transmission data 
    	te_u1c1 = 1;        	        	// Transmission enabled 
}


/**********************************
***  UART1 Initialisierung  *******
**********************************/

void UART1_init(void)
{
	u1mr = 0x05;				// UART1 transmit/receive mode 
	u1c0 = 0x00;				// UART1 transmit/receive control 
	txd1sel=1;
	u1c1 = 0x05;				// Tx, Rx enabled

	ucon = 0x20;				// P00=RXD11,  00100100, 00100000
        u1brg = 130-1;				// 9600 baud @20MHz 
}