/home/daqweb/fgddaq/c8051/Protocols/SPI_handler.c File Reference

#include "../mscbemb.h"
#include "SPI_handler.h"

Functions
void	SPI_Init (void)
void	SPI_ClockOnce (void)
void	SPI_WriteByte (unsigned char dataToSend)
void	SPI_WriteUInt (unsigned int dataToBeSend)
unsigned char	SPI_ReadByteRising (void)
Variables
sbit	SPI_SCK = MSCB_SPI_SCK
sbit	SPI_MISO = MSCB_SPI_MISO
sbit	SPI_MOSI = MSCB_SPI_MOSI

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Function Documentation

void SPI_ClockOnce

(

void

)

Generating the SPI communication clock."SFRPAGE = SPI0_PAGE" makes sure that we are in the right page to properly communicate with the SPI protocol.

Attention:

The SPI clock is currently running at 50us.

{
  SFRPAGE = SPI0_PAGE;
  delay_us(SPI_DELAY);
  SPI_SCK = 1;
  delay_us(SPI_DELAY);
  SPI_SCK = 0;
}

void SPI_Init

(

void

)

Initializing the SPI communication by pulling the SPI Master Output Slave Input (MOSI) pin to 1.

{
  SFRPAGE  = SPI0_PAGE ;
  SPI_MOSI = 1;          //pull the MOSI line high
#ifdef AD5300
  SPI_SCK = 1;
#endif
}

unsigned char SPI_ReadByteRising

(

void

)

{
  signed char i = 0;
  unsigned char din = 0;
  unsigned char dataReceived = 0;

  SFRPAGE = SPI0_PAGE ;
  for(i = 7; i >= 0; i--)
  {
        delay_us(SPI_DELAY);
   din = SPI_MISO;
   dataReceived |= (din << i);
        SPI_SCK = 1;
        delay_us(SPI_DELAY);
        SPI_SCK = 0;
 
  }
  return dataReceived;
}

void SPI_WriteByte

(

unsigned char

dataToSend

)

Performing SPI write operation.One byte of data transmits in a bit wise fashion

Parameters:

dataToSend

One byte of information which has to be sent via SPI protocol.

Returns:

The function does not return any value.

{
  signed char i;

  SFRPAGE = SPI0_PAGE ;
  for(i = 7; i >= 0; i--) {
     SPI_MOSI = (dataToSend >> i) & 0x01;
     SPI_ClockOnce();
  }
  SPI_MOSI = 0;
}

void SPI_WriteUInt

(

unsigned int

dataToBeSend

)

Performing SPI write operation.Two bytes of data transmits in a bit wise fashion

Parameters:

dataToSend

Two byte of information which has to be sent via SPI protocol.

Returns:

The function does not return any value.

{
        signed char i;
        
  SFRPAGE = SPI0_PAGE ;
  
  for(i = 15; i >= 0; i--) {       
          SPI_MOSI = (dataToBeSend >> i) & 0x01;
     SPI_ClockOnce();
  }
  SPI_MOSI = 0;
}

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Variable Documentation

sbit SPI_MISO = MSCB_SPI_MISO

sbit SPI_MOSI = MSCB_SPI_MOSI

sbit SPI_SCK = MSCB_SPI_SCK

Setting the related pins of SPI protocol

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