SPI Master


	//----- SETUP SPI 1 -----
	//Used for: 
	w_temp = SPI1BUF;
	SPI1STAT = 0;
	SPI1CON1 = 0b0000001100100001;	//SPI in master mode (SPI1STATbits.SPIEN must be 0 to write to this register)
									//Data is valid on the rising edge of the clock (Transmit occurs on transition from active to idle clock state)
									//Clock low in idle bus state
	SPI1CON1bits.PPRE1 = 1;			//Prescallers 4:1 1:1 = 10MHz (max possible from this device)
	SPI1CON1bits.PPRE0 = 0;
	SPI1CON1bits.SPRE2 = 1;
	SPI1CON1bits.SPRE1 = 1;
	SPI1CON1bits.SPRE0 = 1;
	SPI1CON2 = 0;
	SPI1STATbits.SPIEN = 1;			//Enable the port

 

SPI Slave

Initialise

	//----- SETUP SPI 2 -----
	//Used for: 
	SPI2BUF = 0;
	IFS2bits.SPI2IF = 0;			//Clear the Interrupt Flag
	IEC2bits.SPI2IE = 0;			//Disable The Interrupt

	SPI2CON1bits.DISSCK = 0;		//Internal Serial Clock is Enabled
	SPI2CON1bits.DISSDO = 0;		//SDOx pin is controlled by the module
	SPI2CON1bits.MODE16 = 0;		//Communication is byte-wide (8 bits)
	SPI2CON1bits.SMP = 0;			//Input Data is sampled at the middle of data Output time
	SPI2CON1bits.CKE = 1;			//Data is valid on the rising edge of the clock (Transmit occurs on transition from active to idle clock state)
	SPI2CON1bits.CKP = 0;			//Clock low in idle bus state
	SPI2CON1bits.MSTEN = 0;			//Master Mode disabled
	SPI2CON1bits.SSEN = 1;			//SS pin enabled (the SSx pin must be enabled in Slave mode when CKE = 1)
	SPI2STATbits.SPIROV =0;			//No Receive Overflow has Occurred
	SPI2STATbits.SPIEN = 1;			//Enable SPI Module
	
	IFS2bits.SPI2IF = 0;			//Clear the Interrupt Flag
	IEC2bits.SPI2IE = 1;			//Enable The Interrupt
Interrupt


//***************************************
//***************************************
//********** SPI2 RX INTERRUPT **********
//***************************************
//***************************************
void __attribute__((__interrupt__,__auto_psv__)) _SPI2Interrupt(void)
{
	WORD data;

	if (SPI2STATbits.SPIROV)
	{
		//----- OVERFLOW ERROR -----
		//If a new data word has been shifted into SPIxSR and the previous SPIxBUF contents have not been read, the SPIROV bit (SPIxSTAT<6>) is set.
		//Any received data in SPIxSR is not transferred, and further data reception is disabled until the SPIROV bit is cleared. The SPIROV bit is not
		//cleared automatically by the module; it must be cleared by the user application.
		data = SPI2BUF;
		SPI2STATbits.SPIROV = 0;
		IFS2bits.SPI2IF = 0;			//Clear the Interrupt Flag
		return;
	}

	//----- READ THE DATA -----
	data = SPI2BUF;

	//----- WRITE THE NEXT DATA BYTE -----
	//This needs to happen befoer the next byte/word is received.  This irq is triggered 1/2 bit time before the end of the last bit of this byte/word, so if the master is fast we must service to her before the start of the first bit of the next byte/word.
	SPI2BUF = data + 1;			//Send back what we received + 1
	
	IFS2bits.SPI2IF = 0;			//Clear the Interrupt Flag
}

//******************************************
//******************************************
//********** SPI2 ERROR INTERRUPT **********
//******************************************
//******************************************
//SPIx Error Interrupt Flag (SPIxEIF) is set when the SPIROV bit is set. This interrupt flag must be cleared in software. The actual SPIx Error Interrupt
//is generated only when the corresponding SPIxEIE bit is set in the IECn Control register.
/*
void __attribute__((__interrupt__,__auto_psv__)) _SPI2ErrInterrupt(void)
{
	
}
*/

 

 

USEFUL?
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