Uses DMA to read/write SPI blocks, while putting the current thread in Wait state.
Diff: RTOS_SPI_KL25.cpp
- Revision:
- 1:d021fb155bff
- Parent:
- 0:004e5e86de4e
- Child:
- 2:d052724e2ad6
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/RTOS_SPI_KL25.cpp Sun Jan 05 10:20:17 2014 +0000 @@ -0,0 +1,39 @@ +#ifdef TARGET_KL25Z +#include "RTOS_SPI.h" + +RTOS_SPI::RTOS_SPI(PinName mosi, PinName miso, PinName sclk, PinName _unused) : SPI(mosi, miso, sclk) { + if (_spi.spi == SPI0) { + read_dma.trigger(Trigger_SPI0_RX); + write_dma.trigger(Trigger_SPI0_TX); + } else { + read_dma.trigger(Trigger_SPI1_RX); + write_dma.trigger(Trigger_SPI1_TX); + } + + read_dma.source(&_spi.spi->D, false); + write_dma.destination(&_spi.spi->D, false); +}; + +void RTOS_SPI::bulkInternal(uint8_t *read_data, uint8_t *write_data, int length, bool read_inc, bool write_inc) { + aquire(); + _spi.spi->C2 |= SPI_C2_TXDMAE_MASK | SPI_C2_RXDMAE_MASK; + + read_dma.destination(read_data, read_inc); + if (write_inc) + write_dma.source(write_data+1, write_inc); + else + write_dma.source(write_data, write_inc); + + //simply start the read_dma + read_dma.start(length); + + //Write the first byte manually, since this is recommended method (and the normal method sends the first byte twice) + while((_spi.spi->S & SPI_S_SPTEF_MASK) == 0); + _spi.spi->D = write_data[0]; + + write_dma.wait(length-1); + while(read_dma.isBusy()); + + _spi.spi->C2 &= ~(SPI_C2_TXDMAE_MASK | SPI_C2_RXDMAE_MASK); +} +#endif \ No newline at end of file