Merge pull request #14 from FrankBoesing/T4-support

T4 support

utility/Sd2Card.cpp

 }
 /** SPI send multiple bytes */
 
-
-
+#elif defined(__IMXRT1052__)  || defined(__IMXRT1062__)
+ #define USE_TEENSY4_SPI
+ 
+ static void spiInit(uint8_t spiRate) {
+  switch (spiRate) {
+    // the top 2 speeds are set to 24 MHz, for the SD library defaults
+    case 0:  settings = SPISettings(25200000, MSBFIRST, SPI_MODE0); break;
+    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;
+    case 4:  settings = SPISettings(3000000, MSBFIRST, SPI_MODE0); break;
+    case 5:  settings = SPISettings(2000000, MSBFIRST, SPI_MODE0); break;
+    default: settings = SPISettings(400000, MSBFIRST, SPI_MODE0);
+  }
+  SPI.begin();
+} 
+
+ static void spiSend(uint8_t b) {
+	SPI.transfer(b);
+ }
+ 
+ static  uint8_t spiRec(void) {
+	return SPI.transfer(0xff);
+ }
+ 
+ static void spiRec(uint8_t* buf, size_t len) {
+	SPI.transfer(buf, len);	
+ }
+ 
+ static void spiRecIgnore(size_t len) {
+	for (size_t i=0; i < len; i++) 
+		SPI.transfer(0xff);
+ }
+ 
 //------------------------------------------------------------------------------
 #else
 // functions for hardware SPI
   pinMode(chipSelectPin_, OUTPUT);
   digitalWrite(chipSelectPin_, HIGH);
 
-#ifdef USE_TEENSY3_SPI
+#if defined(USE_TEENSY3_SPI)
   spiBegin();
   spiInit(6);
+#elif defined(USE_TEENSY4_SPI)
+  spiInit(6);
+  pinMode(SS_PIN, OUTPUT);
+  digitalWrite(SS_PIN, HIGH); // disable any SPI device using hardware SS pin  
 #else
   // set pin modes
   pinMode(SPI_MISO_PIN, INPUT);
   settings = SPISettings(250000, MSBFIRST, SPI_MODE0);
 #endif
 #endif  // not USE_TEENSY3_SPI
-
   // must supply min of 74 clock cycles with CS high.
 #ifdef SPI_HAS_TRANSACTION
   SPI.beginTransaction(settings);
 #ifdef SPI_HAS_TRANSACTION
   SPI.endTransaction();
 #endif
-
   chipSelectLow();
-
   // command to go idle in SPI mode
   while ((status_ = cardCommand(CMD0, 0)) != R1_IDLE_STATE) {
     unsigned int d = millis() - t0;
   }
   // initialize card and send host supports SDHC if SD2
   arg = (type_ == SD_CARD_TYPE_SD2) ? 0X40000000 : 0;
-
   while ((status_ = cardAcmd(ACMD41, arg)) != R1_READY_STATE) {
     // check for timeout
     unsigned int d = millis() - t0;
   if (!waitStartBlock()) {
     goto fail;
   }
-#ifdef USE_TEENSY3_SPI
+#if defined(USE_TEENSY3_SPI) | defined(USE_TEENSY4_SPI)
   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) {
-#ifdef USE_TEENSY3_SPI
+#if defined(USE_TEENSY3_SPI) || defined(USE_TEENSY4_SPI)
   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) {
-#ifdef OPTIMIZE_HARDWARE_SPI
+#if defined(OPTIMIZE_HARDWARE_SPI) && !defined(USE_TEENSY4_SPI)
 
   // send data - optimized loop
   SPDR = token;
 #else  // OPTIMIZE_HARDWARE_SPI
   spiSend(token);
   for (uint16_t i = 0; i < 512; i++) {
-    spiSend(src[i]);
+    spiSend(src[i]); 
   }
 #endif  // OPTIMIZE_HARDWARE_SPI
   spiSend(0xff);  // dummy crc

utility/Sd2PinMap.h

 #ifndef Sd2PinMap_h
 #define Sd2PinMap_h
 
-#if defined(__arm__) || defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MK64FX512__) || defined(__MK66FX1M0__)
+#if defined(__arm__) || defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MK64FX512__) || defined(__MK66FX1M0__) || defined(__IMXRT1052__)  || defined(__IMXRT1062__)
 
 #include <Arduino.h>