ad1836.c

VisualDSP++4.0

//--------------------------------------------------------------------------//
// Header files																//
//--------------------------------------------------------------------------//
#include <sys\exception.h>
#include <cdefBF561.h>
#include <ccblkfn.h>
#include <sysreg.h>

#include "TDMchannels.h"
#include "AD1836defaults.h"
#include "sport0_isr.h"

//--------------------------------------------------------------------------//
// Symbolic constants used in the initialization routines					//
//--------------------------------------------------------------------------//
// AD1836 reset PF15
#define AD1836_RESET_bit 15

// SPI transfer mode
#define TIMOD_DMA_TX 0x0003

// SPORT0 word length
#define SLEN_32	0x001f

// DMA flow mode
#define FLOW_1	0x1000

//--------------------------------------------------------------------------//
// Variables																//
//																			//
// Description:	The global variables  iADCnC contain the data coming from	//
//				the codec AD1836.  The (processed) playback data are written//
//				into the variables iDACnC, which are then sent back to the	//
//				codec in the SPORT0 ISR.							  		//
//																			//
//				The values in the array sAD1836TxRegs can be modified to 	//
//				set up the codec in different configurations according to   //
//				the AD1836 data sheet.										//
//--------------------------------------------------------------------------//
// global integers (32bit) for access to the ADC/DAC samples by the application code
int iADC1L, iADC1R, iADC2L, iADC2R;
int iDAC1L, iDAC1R, iDAC2L, iDAC2R, iDAC3L, iDAC3R;

// global adress of the SPI transfer array for codec register value transfer
// The values will be set to default values in AD1836default.h so that no
// initialisation with the SET__AD1836_* macros is necessary for a default
// configuration of the codec.

// size of array sAD1836TxRegs
#define AD1836_REGS_LENGTH	11

volatile unsigned short sAD1836TxRegs[AD1836_REGS_LENGTH] =
{									
	(DAC_CONTROL_1_ADR << 0xC ) | DAC_CONTROL_1_FCT,
	(DAC_CONTROL_2_ADR << 0xC ) | DAC_CONTROL_2_FCT,
	(DAC1L_VOLUME_ADR << 0xC ) | DAC1L_VOLUME_FCT,
	(DAC1R_VOLUME_ADR << 0xC ) | DAC1R_VOLUME_FCT,
	(DAC2L_VOLUME_ADR << 0xC ) | DAC2L_VOLUME_FCT,
	(DAC2R_VOLUME_ADR << 0xC ) | DAC2R_VOLUME_FCT,
	(DAC3L_VOLUME_ADR << 0xC ) | DAC3L_VOLUME_FCT,
	(DAC3R_VOLUME_ADR << 0xC ) | DAC3R_VOLUME_FCT,
	(ADC_CONTROL_1_ADR << 0xC ) | ADC_CONTROL_1_FCT,
	(ADC_CONTROL_2_ADR << 0xC ) | ADC_CONTROL_2_FCT,
	(ADC_CONTROL_3_ADR << 0xC ) | ADC_CONTROL_3_FCT					
};

//--------------------------------------------------------------------------//
// Prototypes																//
//--------------------------------------------------------------------------//

void InitAD1836(void);
void Init_Sport0(void);
void Init_DMA(void);
void Init_Sport_Interrupts(void);
void Enable_DMA_Sport0(void);
EX_INTERRUPT_HANDLER(Sport0_RX_ISR);


//--------------------------------------------------------------------------//
// Function:	start_AD1836()												//
//																			//
// Description:	This function serves as interface to the application code,	//
//				it just calls all the individual initialisation functions	//
//--------------------------------------------------------------------------//

void start_AD1836(void) {
	InitAD1836();				// initialize codec
	Init_Sport0();				// initialize serial port 0 for data transfer
	Init_DMA();					// initialize DMA for data transfer
	Init_Sport_Interrupts();	// initialize interrupts from serial port 0
	Enable_DMA_Sport0();		// enable DMA transfer to/from serial port 0
}

//--------------------------------------------------------------------------//
// Function:	InitAD1836()												//
//																			//
// Description:	This function sets up the SPI port to configure the AD1836. //
//				The content of the array sAD1836TxRegs is sent to the 		//
//				codec.														//
//--------------------------------------------------------------------------//

void InitAD1836(void)
{
	int wait_reset;
	int wait_dma_finish;

	// reset codec
		// set PF15 as output
		*pFIO0_DIR |= (1 << AD1836_RESET_bit); 
		ssync();
		// clear bit to enable AD1836
		*pFIO0_FLAG_S |= (1 << AD1836_RESET_bit);	
		ssync();

	// wait to recover from reset
		for (wait_reset=0; wait_reset<0xf000; wait_reset++);

	// configure SPI for transfer of control registers via DMA
		// enable PF4
		*pSPI_FLG = FLS4;
		// set baud rate SCK = HCLK/(2*SPIBAUD)	
		*pSPI_BAUD = 16;
		// SPI DMA write, 16-bit data, MSB first, SPI Master
		*pSPI_CTL = TIMOD_DMA_TX | SIZE | MSTR;
		// Set up DMA2 channel 4 to SPI transmit
		*pDMA2_4_PERIPHERAL_MAP = 0x4000;
		// Configure DMA2 channel4 for 16 bit transfers
		*pDMA2_4_CONFIG = WDSIZE_16;
		// Start address of data buffer
		*pDMA2_4_START_ADDR = (void*) sAD1836TxRegs;
		// DMA inner loop count
		*pDMA2_4_X_COUNT = AD1836_REGS_LENGTH;
		// Inner loop address increment
		*pDMA2_4_X_MODIFY = 2;
	
	// enable DMAs
		*pDMA2_4_CONFIG = (*pDMA2_4_CONFIG | DMAEN);
	// enable spi
		*pSPI_CTL = (*pSPI_CTL | SPE);
		ssync();
	
	// wait until dma transfers for spi are finished 
		for (wait_dma_finish=0; wait_dma_finish<0xaff; wait_dma_finish++);
	
	// disable spi
		*pSPI_CTL = 0x0000;
		
	// transfer of control data via DMA and SPI to codec control registers completed
}

//--------------------------------------------------------------------------//
// Function:	Init_Sport0													//
//																			//
// Description:	Configure Sport0 for TDM mode, to transmit/receive data 	//
//				to/from the AD1836. Configure Sport for external clocks and //
//				frame syncs.												//
//--------------------------------------------------------------------------//

void Init_Sport0(void)
{
	// Sport0 receive configuration
	// External CLK, External Frame sync, MSB first
	// 32-bit data
	*pSPORT0_RCR1 = RFSR;
	*pSPORT0_RCR2 = SLEN_32;
	
	// Sport0 transmit configuration
	// External CLK, External Frame sync, MSB first
	// 24-bit data
	*pSPORT0_TCR1 = TFSR;
	*pSPORT0_TCR2 = SLEN_32;
	
	// Enable MCM 8 transmit & receive channels
	*pSPORT0_MTCS0 = 0x000000FF;
	*pSPORT0_MRCS0 = 0x000000FF;
	
	// Set MCM configuration register and enable MCM mode
	*pSPORT0_MCMC1 = 0x0000;
	*pSPORT0_MCMC2 = 0x101c;
}


//--------------------------------------------------------------------------//
// Function:	Init_DMA													//
//																			//
// Description:	Initialize DMA2_0 in autobuffer mode to receive and DMA2_1 	//
//				in autobuffer mode to transmit								//
//--------------------------------------------------------------------------//

void Init_DMA(void)
{
	// Set up DMA2 channel 0 to Sport receive
	*pDMA2_0_PERIPHERAL_MAP = 0x0000;

	// Configure DMA2 channel0
	// 32-bit transfers, Interrupt on completion, Autobuffer mode
	*pDMA2_0_CONFIG = WNR | WDSIZE_32 | DI_EN | FLOW_1;
	// Start address of data buffer
	*pDMA2_0_START_ADDR = (void*) iDMARxBuffer;
	// DMA inner loop count
	*pDMA2_0_X_COUNT = 8;
	// Inner loop address increment
	*pDMA2_0_X_MODIFY	= 4;
	
	
	// Set up DMA2 channel 1 to Sport transmit
	*pDMA2_1_PERIPHERAL_MAP = 0x1000;
	
	// Configure DMA2 channel 1
	// 32-bit transfers, Autobuffer mode
	*pDMA2_1_CONFIG = WDSIZE_32 | FLOW_1;
	// Start address of data buffer
	*pDMA2_1_START_ADDR = (void*) iDMATxBuffer;
	// DMA inner loop count
	*pDMA2_1_X_COUNT = 8;
	// Inner loop address increment
	*pDMA2_1_X_MODIFY	= 4;
}


//--------------------------------------------------------------------------//
// Function:	Init_Interrupts												//
//																			//
// Description:	Initialize Interrupt for Sport0 RX							//
//--------------------------------------------------------------------------//
void Init_Sport_Interrupts(void)
{
	// assign interrupt channel 23 (DMA2_0) to IVG9 
	*pSICA_IAR2 = Peripheral_IVG(23,9);	
	
	// assign ISRs to interrupt vectors
	// Sport0 RX ISR -> IVG 9
	register_handler(ik_ivg9, Sport0_RX_ISR);		

	// clear pending IVG9 interrupts
	*pILAT |= EVT_IVG9;		
	ssync();
	
	// enable Sport0 RX interrupt
	*pSICA_IMASK0 |= SIC_MASK(23);
	ssync();
	
}


//--------------------------------------------------------------------------//
// Function:	Enable_DMA_Sport 0											//
//																			//
// Description:	Enable DMA2_0, DMA2_1, Sport0 TX and Sport0 RX				//
//--------------------------------------------------------------------------//
void Enable_DMA_Sport0(void)
{
	// enable DMAs
	*pDMA2_1_CONFIG	= (*pDMA2_1_CONFIG | DMAEN);
	*pDMA2_0_CONFIG	= (*pDMA2_0_CONFIG | DMAEN);
	
	// enable Sport0 TX and RX
	*pSPORT0_TCR1 	= (*pSPORT0_TCR1 | TSPEN);
	*pSPORT0_RCR1 	= (*pSPORT0_RCR1 | RSPEN);
}