dmaSPIslave.h

00001 #ifndef DMASPISLAVE_H    // To make sure you don't declare the function more than once by including the header multiple times.
00002 #define DMASPISLAVE_H
00003 
00004 #ifdef TARGET_KL46Z
00005 class dmaSPISlave : public SPISlave{
00006     public:
00007 /*
00008 @brief:     constructor : initialise the spi slave pins
00009 @param:     mosi, miso, sclk, ssel
00010 @return:    none
00011 */
00012         dmaSPISlave(PinName mosi, PinName miso, PinName sclk, PinName ssel) : SPISlave(mosi, miso, sclk, ssel){
00013 //            trigger appropriate spi for dma
00014             if(_spi.spi == SPI0){
00015                 read_dma.trigger(Trigger_SPI0_RX);
00016             }
00017             else{
00018                 read_dma.trigger(Trigger_SPI1_RX);
00019             }
00020             
00021 //            set source for spi slave dma : mosi
00022             read_dma.source(&_spi.spi->DL, false);
00023         }
00024         
00025 /*
00026 @brief:     initialise the dma buffer to store the recevied data
00027 @param:     read_data : pointer to the buffer
00028             len : length in bytes to store in the buffer
00029             fun : address of the function to attach to the dma interrupt, interrupt is called when the len num of bytes are written to the buffer
00030 @return:    none
00031 */
00032         void bulkRead_init(uint8_t *read_data, int len, void (*fun)(void) ){
00033 //            acquire();
00034             _spi.spi->C2 |= SPI_C2_RXDMAE_MASK;
00035         
00036 //            auto increment is true
00037             read_dma.destination(read_data, true);
00038         
00039 //            specify length
00040             length = len;
00041             
00042 //            attach interrupt function
00043             read_dma.attach(fun);
00044 
00045         }
00046         
00047         void bulkRead_pause(){
00048             read_dma.attach(NULL);
00049             }
00050             
00051         void bulkRead_resume(void (*fun)(void)){
00052             read_dma.attach(fun);
00053             }
00054 /*
00055 @brief:     start the dma read process : has to be done everytime the buffer gets filled, can be used repeatedly
00056 @param:     none
00057 @return:    none
00058 */
00059         void bulkRead_start(){
00060 //            start the read_dma
00061             read_dma.start(length);
00062         }
00063 
00064 /*
00065 @brief:     end dma process and return back to normal spi mode, there should not be an unfinished 'start' when running end
00066 @param:     none
00067 @return:    none
00068 */
00069         void bulkRead_end(){
00070 //            turn off dma
00071             _spi.spi->C2 &= ~(SPI_C2_RXDMAE_MASK);
00072         }
00073         
00074 /*
00075 @brief:     restart the dma process after 'end'ing
00076 @param:     none
00077 @return:    none
00078 */
00079         void bulkRead_restart(){
00080             _spi.spi->C2 |= SPI_C2_RXDMAE_MASK;
00081         }
00082     private:
00083         int length;
00084         SimpleDMA read_dma;
00085 };
00086 #endif
00087 #endif