Uses DMA to read/write SPI blocks, while putting the current thread in Wait state.

Dependencies:   SimpleDMA

Dependents:   SDFileSystem-RTOS

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