SPI slave operation using F28335.

Hello!

I would recommend you DM (p.95) 0743.TI_TMS320f28332-35_manual.pdf.

Regards,

Igor

Hi,

Download controlSuite from TI website. It consists of numerous examples on SPI communication.

Regards,

Gautam

Hello Igor , Gautham,

Thanks for reply.

I looked at manual and in Controlsuite i found loopback example.

in loop back, if i change control register to

SPICTL.all = 0;
SPICTL.bit.OVERRUNINTENA = 0; // enable receiver overrun interrupts
SPICTL.bit.CLK_PHASE = 0; // normal SPI clocking scheme (mode polarity 0 - phase 0)
SPICTL.bit.MASTER_SLAVE = 0; // SPI configured as slave
SPICTL.bit.TALK = 1; // enable data transmission
SPICTL.bit.SPIINTENA = 1; // enable SPI interrupts

and also loopback register, is it ok.

Hello Venkat!

For more detailed information you can refer to this Reference Guide 3000.TI_SPI_2833x_sprueu3a.pdf.

Regards,

Igor

Hello,

We wanna implement SPI slave in F28335. we tired to modify the example available and got something like below code.

Can any one please let me, where are we doing mistake. 

thanks,

suraj.

#include "DSP28x_Project.h" 

interrupt void spiTxFifoIsr(void);

void spi_xmt(Uint16 a);
void delay_loop(void);
void spi_fifo_init(void);
void error();

void main(void)
{
    Uint16 i,j;

  InitSysCtrl();

InitSpiaGpio();

DINT;
IER = 0x0000;
IFR = 0x0000;

InitPieCtrl();

InitPieVectTable();

EALLOW;

PieVectTable.SPIRXINTA = &spiRxFifoIsr;
PieVectTable.SPITXINTA = &spiTxFifoIsr;
EDIS;

spi_fifo_init();

PieCtrlRegs.PIECTRL.bit.ENPIE = 1; // Enable the PIE block
PieCtrlRegs.PIEIER6.bit.INTx1=1; // Enable PIE Group 6, INT 1
PieCtrlRegs.PIEIER6.bit.INTx2=1; // Enable PIE Group 6, INT 2
IER=0x20; // Enable CPU INT6
EINT;

 while(1)
 {
    i++;
    if(i%5000000 == 0)
    {

     for(j=0x40;j<0x4d;j++)
    {
     spi_xmt(j);
     }

   }

 }

 }

void delay_loop()
{
long i;
for (i = 0; i < 1000000; i++) {}
}

void error(void)
{
asm(" ESTOP0"); //Test failed!! Stop!
for (;;);
}

void spi_fifo_init()
{
// Initialize SPI FIFO registers
SpiaRegs.SPICCR.bit.SPISWRESET=0; // Reset SPI

//SpiaRegs.SPICCR.all=0x001F; //16-bit character, Loopback mode
SpiaRegs.SPICCR.bit.CLKPOLARITY = 0;
SpiaRegs.SPICCR.bit.SPILBK = 0; // disable loopback
SpiaRegs.SPICCR.bit.SPICHAR = 7; //8-bit character

//SpiaRegs.SPICTL.all=0x0017; //Interrupt enabled, Master/Slave XMIT enabled
SpiaRegs.SPICTL.bit.SPIINTENA = 1; // Interrupt disable
SpiaRegs.SPICTL.bit.TALK = 1; // Transmit enable
SpiaRegs.SPICTL.bit.MASTER_SLAVE = 0; //Slave
SpiaRegs.SPICTL.bit.CLK_PHASE = 0; //Normal phase, depending on SPICCR.6 (CLOCK_POLARITY)
SpiaRegs.SPICTL.bit.OVERRUNINTENA = 1; //Overrun interrupt disable

SpiaRegs.SPISTS.all=0x0000;
SpiaRegs.SPIBRR=0x0063; // Baud rate
SpiaRegs.SPIFFTX.all=0xC028; // Enable FIFO's, set TX FIFO level to 8
SpiaRegs.SPIFFRX.all=0x0028; // Set RX FIFO level to 8
SpiaRegs.SPIFFCT.all=0x00;
SpiaRegs.SPIPRI.all=0x0010;

SpiaRegs.SPICCR.bit.SPISWRESET=1; // Enable SPI

SpiaRegs.SPIFFTX.bit.TXFIFO=0;
SpiaRegs.SPIFFRX.bit.RXFIFORESET=1;
}

interrupt void spiTxFifoIsr(void)
{
Uint16 i;
for(i=0;i<8;i++)
{
SpiaRegs.SPITXBUF=sdata[i]; // Send data
}

for(i=0;i<8;i++) // Increment data for next cycle
{
sdata[i]++;
}

SpiaRegs.SPIFFTX.bit.TXFFINTCLR=1; // Clear Interrupt flag
PieCtrlRegs.PIEACK.all|=0x20; // Issue PIE ACK
}

void spi_xmt(Uint16 a)
{
Uint16 dummy;

while(SpiaRegs.SPIFFTX.bit.TXFFST ==16);
SpiaRegs.SPITXBUF=a;
dummy = SpiaRegs.SPIRXBUF ;
}

Hello,

Can anyone please let me know, whether where am i doing mistake.

Thanks,

suraj.