/****************************************************************************
* DESCRIPTION:    
*   Sample program for the eZdsp33.  This example can  generate
*   loop the analog input to output. 
*   The eZdsp33 operates the VC33 in Microcontroller/Bootloader mode.
*   This means that interrupts are double vectored with user interrupts
*   located on-chip at addresses 0x809FC1-0x809FFF.
****************************************************************************/
#define vc33dsk_c 
#include <stdlib.h>      
/*---------------------------------------------------------------------------- 
* Serial port 0 regisiter addresses
*---------------------------------------------------------------------------*/     
#define SP0_BASE            0x808040   
#define SP_GLB_CNTL    	    0x0 	
#define SP_FSX_CNTL         0x2 
#define SP_FSR_CNTL         0x3 
#define SP_RX_TIM_CNTL      0x4 
#define SP_RX_TIM_CNTR      0x5 
#define SP_RX_TIM_PRD       0x6 
#define SP_XMIT             0x8 
#define SP_RECV             0xC         
#define SP_RESET           0x00170300                                  
#define SP_AD50_GLB_CNTL   0x4E170300
#define SP_AD50_FSX_CNTL   0x00000111
#define SP_AD50_FSR_CNTL   0x00000111                 
#define ISR_BASE           0x00809FC0     /* Base of VC33 redir. int. table*/ 
/*-- Redirected interrupt offset for basic interrupts. --------------------*/ 
enum WHICH_ISR
{    
    Reset = 0,         
	Int0,
	Int1,
	Int2,
	Int3,
	Xint0,
	Rint0,
	Resv0,
	Resv1,
	Tint0,
	Tint1,
	Dint0,
	Dint1
};            
/*---- data declarations ---------------------------------------------------*/


volatile unsigned int Data_rx = 0;
volatile unsigned int Data_tx = 0;



/*---------------------------------------------------------------------------
* PUBLIC FUNCTION DEFINITIONS
*----------------------------------------------------------------------------  
* NAME:  void  IsrInstall( int IsrNum, void( *Isr)( void) )  
*        Install an interrupt into ISR table.                        
*---------------------------------------------------------------------------*/
void 
IsrInstall( int IsrNum, void( *Isr)( void) )
{    
	unsigned * IsrBase = (unsigned *)ISR_BASE;
	unsigned   IsrAddr = (unsigned)Isr;
	IsrAddr &= 0x00FFFFFF;
	IsrAddr |= 0x60000000;
	IsrBase[IsrNum] = IsrAddr;    
}   
/*-------------------------------------------------------------------------
* NAME: interrupt  void isrAdcLoopBack( void )   
*       Loop back the analog input to output. Also stuff the receive 
*       value in the RecvData buffer.    
*--------------------------------------------------------------------------*/
interrupt 
void isrAdcLoopBack( void )
{    
 /*----------------------------------------------------------------------- 
  * Loop AIN to AOUT.We are masking the upper 16 b. of the data.
  *----------------------------------------------------------------------*/ 
	register unsigned *pSport = (unsigned *)(SP0_BASE);  
	Data_rx =  pSport[SP_RECV] & 0x0000fffe;
	
	pSport[SP_XMIT] = Data_tx;    
	
}                 
/*-----------------------------------------------------------------------
* NAME:   interrupt void FalseInt( void )                   
*         Just a safety valve.           
*-----------------------------------------------------------------------*/
interrupt 
void FalseInt( void )
{
	while( 1 );
}    
/*-----------------------------------------------------------------------
* NAME:   int SetupSerialPort( void )                   
*         Setup the VC33 serial port to work with the AD50.
*-----------------------------------------------------------------------*/
int
SetupSerialPort( void )
{        
	register unsigned *pSport = (unsigned *)SP0_BASE;
	
	volatile register unsigned Rrdy; 
	volatile unsigned Dummy; 
	int i;	   
	/*-- AD50 setup variables. ---------------------------------------------*/
	unsigned Control[4];
	Control[0] = 0x0100;  
	Control[1] = 0x0200;
	Control[2] = 0x0300;
	Control[3] = 0x04C0;	     
	/*-- Set the initial values while in reset -----------------------------*/     
	pSport[SP_GLB_CNTL] = SP_RESET; 
    asm( " NOP " ); 
	asm( " NOP " ); 
	pSport[SP_FSX_CNTL] = SP_AD50_FSX_CNTL; 
	pSport[SP_FSR_CNTL] = SP_AD50_FSR_CNTL; 	
	/*----------------------------------------------------------------------- 
	* The AD50 is the master and continously sends a frame sync.
	* Testing has shown that while the serial port is in reset 
	*-----------------------------------------------------------------------*/ 
	do
	{
		Rrdy =  pSport[SP_FSR_CNTL] & 0x800 ;
	}while( Rrdy != 0); 	      
	do
	{
		Rrdy =  pSport[SP_FSR_CNTL] & 0x800 ;
	}while( Rrdy == 0); 	 
	pSport[SP_GLB_CNTL] = SP_AD50_GLB_CNTL; 
	Dummy = pSport[SP_RECV];   
	pSport[SP_XMIT] = 0;       	 
	/*----------------------------------------------------------------------- 
	* Send the 4 control words to the AD50.  
	*----------------------------------------------------------------------*/ 	 
	for( i=0; i<4; i++ )
	{     
		/*-- Secondary request. -------------------------------------------*/
		do
		{
			Rrdy = pSport[SP_GLB_CNTL];
		}while( ( Rrdy & 1 ) == 0); 
		
		Dummy = pSport[SP_RECV];  
		pSport[SP_XMIT] = 1;      
		asm( " NOP " ); 
		asm( " NOP " );
		asm( " NOP " );		
 		/*-- Control word ------------------------------------------------*/
		do
		{
			Rrdy = pSport[SP_GLB_CNTL];
		}while( ( Rrdy & 1 ) == 0); 		
		Dummy = pSport[SP_RECV];        
		pSport[SP_XMIT] = Control[i];  
	} 	
	/*----------------------------------------------------------------------- 
	* Dummy cycle to get xmitter filled with 0 and empty
	* the receiver.  
	*----------------------------------------------------------------------*/ 	 
	do
	{
		Rrdy = pSport[SP_GLB_CNTL];
	}while( ( Rrdy & 1 ) == 0); 
	
	Dummy = pSport[SP_RECV];      
	pSport[SP_XMIT] = 0;             				
	return(0);
} 
/*-----------------------------------------------------------------------------
* NAME:   void MemSetWaitStates( int WaitStates )                   
*         Set the VC33 primary-bus control register.
*-----------------------------------------------------------------------------*/    
void 
MemSetWaitStates( int WaitStates )
{
	unsigned  *pMemCntl = (unsigned *)0x808064;
	unsigned   MemCntl;	
	MemCntl = *pMemCntl;
	MemCntl &= ~( 7<<5);
	MemCntl |= (WaitStates & 7) << 5;	
	*pMemCntl = MemCntl;	
}  
/*-----------------------------------------------------------------------------
* NAME:  void  main( void )                   
*        The main example.
*-----------------------------------------------------------------------------*/     
void 
main( void )
{                    
    float prom = 0.0 ;
   
    IsrInstall( Rint0, isrAdcLoopBack );   
    /*-- Set up the serial port for use with the AD50. ---------------------*/                                          
    SetupSerialPort();        
    /*-- Enable interrupts. ------------------------------------------------*/     
    asm( " xor ie,ie ");
    asm( " xor if,if ");    
    asm( " or  00320h,ie ");
    asm( " or  02000h,st ");
    /*-- Loop processing interrupts. ---------------------------------------*/   
 	while( 1 )
 	{       
 		/*	prom = prom + 0.1;
 			Data_tx = (unsigned int) prom; */
 			
 			Data_tx = Data_tx + 10;
 			
 			if (Data_tx > 32000) 
 			{
 				Data_tx = 0;
 			}
 				
 			asm( " idle " );    
 			
 	} 
}