Merge pull request #22 from rutmarti/master

Use SPI library for Teensy LC

utility/Sd2Card.cpp

 }
 /** SPI send multiple bytes */
 
-#elif defined(__IMXRT1052__)  || defined(__IMXRT1062__)
- #define USE_TEENSY4_SPI
+#elif defined(__IMXRT1052__)  || defined(__IMXRT1062__) || defined(__MKL26Z64__)
+ #define USE_SPI_LIB
  
  static void spiInit(uint8_t spiRate) {
   switch (spiRate) {
+#ifdef __MKL26Z64__
+    // the top 2 speeds are set to 24 MHz, for the SD library defaults
+    case 0:  settings = SPISettings(24000000, MSBFIRST, SPI_MODE0); break;
+#else
     // the top 2 speeds are set to 24 MHz, for the SD library defaults
     case 0:  settings = SPISettings(25200000, MSBFIRST, SPI_MODE0); break;
+#endif
     case 1:  settings = SPISettings(24000000, MSBFIRST, SPI_MODE0); break;
     case 2:  settings = SPISettings(8000000, MSBFIRST, SPI_MODE0); break;
     case 3:  settings = SPISettings(4000000, MSBFIRST, SPI_MODE0); break;
 #if defined(USE_TEENSY3_SPI)
   spiBegin();
   spiInit(6);
-#elif defined(USE_TEENSY4_SPI)
+#elif defined(USE_SPI_LIB)
   spiInit(6);
   pinMode(SS_PIN, OUTPUT);
   digitalWrite(SS_PIN, HIGH); // disable any SPI device using hardware SS pin  
   if (!waitStartBlock()) {
     goto fail;
   }
-#if defined(USE_TEENSY3_SPI) | defined(USE_TEENSY4_SPI)
+#if defined(USE_TEENSY3_SPI) | defined(USE_SPI_LIB)
   spiRec(dst, 512);
   spiRecIgnore(2);
 #else  // OPTIMIZE_HARDWARE_SPI
  * false, is returned for an invalid value of \a sckRateID.
  */
 uint8_t Sd2Card::setSckRate(uint8_t sckRateID) {
-#if defined(USE_TEENSY3_SPI) || defined(USE_TEENSY4_SPI)
+#if defined(USE_TEENSY3_SPI) || defined(USE_SPI_LIB)
   spiInit(sckRateID);
   return true;
 #else
 //------------------------------------------------------------------------------
 // send one block of data for write block or write multiple blocks
 uint8_t Sd2Card::writeData(uint8_t token, const uint8_t* src) {
-#if defined(OPTIMIZE_HARDWARE_SPI) && !defined(USE_TEENSY4_SPI)
+#if defined(OPTIMIZE_HARDWARE_SPI) && !defined(USE_SPI_LIB)
 
   // send data - optimized loop
   SPDR = token;