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void SPI2_DMA_Init(void) {

    DMACON1bits.SSCON0 = 0;

    DMACON1bits.SSCON1 = 0; // DYLINTEN is software programmable

    DMACON1bits.TXINC = 1; // TXADDR is automatically incremented

    DMACON1bits.RXINC = 0; // RXADDR is not automatically incremented

    DMACON1bits.DUPLEX0 = 1;

    DMACON1bits.DUPLEX1 = 0; // Half-duplex mode, transmission only

    DMACON1bits.DLYINTEN = 0; // Interrupt is disabled

    DMACON2bits.DLYCYC = 0b0000; // Delay time of 1 cycle between bytes

    DMACON2bits.INTLVL = 0b0000; // Interrupt on transfer complete

}

void SPI2_DMA_Start(unsigned int length, void* TXADDR, void* RXADDR) {

    // Set length of message to transmit

    DMABCH = (char)(length-1 >> 8);

    DMABCL = (char)(length-1);

    // Set sourcing address

    TXADDRH = (char)((int)TXADDR >> 8);

    TXADDRL = (char)((int)TXADDR);

    // Set receiving address

    RXADDRH = (char)((int)RXADDR >> 8);

    RXADDRL = (char)((int)RXADDR);

    DMACON1bits.DMAEN = 1; // Start transmission

}