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

#include "../mscbemb.h"
#include "CMB_SPI_handler.h"

Functions
void	CMBSPI_Init (void)
void	CMBSPI_ClockOnce (void)
void	CMBSPI_WriteByte (unsigned char dataToSend)
unsigned char	CMBSPI_ReadByteRising (void)
Variables
sbit	CMBSPI_SCK = CMB_SPI_SCK
sbit	CMBSPI_MISO = CMB_SPI_MISO
sbit	CMBSPI_MOSI = CMB_SPI_MOSI

---

Function Documentation

void CMBSPI_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.

{
  delay_us(CMBSPI_DELAY);
  CMBSPI_SCK = 1;
  delay_us(CMBSPI_DELAY);
  CMBSPI_SCK = 0;
}

void CMBSPI_Init

(

void

)

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

{
  SFRPAGE  = SPI0_PAGE ;
  CMBSPI_MOSI = 1;          //pull the MOSI line high
}

unsigned char CMBSPI_ReadByteRising

(

void

)

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

  for(i = 7; i >= 0; i--)
  {
        delay_us(CMBSPI_DELAY);
   din = CMBSPI_MISO;
   dataReceived |= (din << i);
        CMBSPI_SCK = 1;
        delay_us(CMBSPI_DELAY);
        CMBSPI_SCK = 0;
 
  }
  return dataReceived;
}

void CMBSPI_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;

  for(i = 7; i >= 0; i--) {
     CMBSPI_MOSI = (dataToSend >> i) & 0x01;
     CMBSPI_ClockOnce();
  }
  CMBSPI_MOSI = 0;
}

---

Variable Documentation

sbit CMBSPI_MISO = CMB_SPI_MISO

sbit CMBSPI_MOSI = CMB_SPI_MOSI

sbit CMBSPI_SCK = CMB_SPI_SCK

Setting the related pins of SPI protocol

---