--- Sd2Card.cpp	2020-11-27 17:31:58.073651000 +0900
+++ Sd2Card_due.cpp	2021-01-02 09:08:34.772669100 +0900
@@ -52,6 +52,68 @@
 #endif
 }
 #else  // SOFTWARE_SPI
+#ifdef		__SAM3X8E__
+// 1YEN_201109: to use sd card i/f on the tft shield for due
+
+// NOP tune software spi timing
+#define		spi_NOP		__asm__ __volatile__ ("nop")
+// SCK: D13(PB27/NCS3/TIOB0)
+#define		spi_SCK0	REG_PIOB_CODR=(1U<<27)
+#define		spi_SCK1	REG_PIOB_SODR=(1U<<27)
+// MOSI: D11(PD7/A17/BA1/TIOA8)
+#define		spi_MOSI0	REG_PIOD_CODR=(1U<<7)
+#define		spi_MOSI1	REG_PIOD_SODR=(1U<<7)
+// MISO: D12(PD8/A21/NANDALE/TIOB8)
+#define		spi_MISO	(REG_PIOD_PDSR&(1U<<8))
+
+uint8_t	spiRec (void)
+{
+	int		idx;
+	int		data;
+
+	// no interrupts during byte receive - about 1 us
+	noInterrupts ();
+	// output pin high - like sending 0XFF
+	spi_MOSI1;
+	data=0;
+	for (idx=0; idx<8; idx++)
+	{
+		spi_SCK1;
+		data <<= 1;
+		data |= (spi_MISO)? 1: 0;
+
+		spi_SCK0;
+	}
+	// enable interrupts
+	interrupts ();
+
+	return (data);
+}
+
+void	spiSend (
+uint8_t		data)
+{
+	int		idx;
+
+	// no interrupts during byte send - about 1 us
+	noInterrupts ();
+	for (idx=0; idx<8; idx++)
+	{
+		spi_SCK0;
+		if (data&0x80)
+			spi_MOSI1;
+		else
+			spi_MOSI0;
+		data <<= 1;
+		
+		spi_SCK1;
+	}
+	spi_SCK0;
+	// enable interrupts
+	interrupts ();
+}
+#undef	USE_SPI_LIB
+#else	//	__SAM3X8E__
 //------------------------------------------------------------------------------
 /** nop to tune soft SPI timing */
 #define nop asm volatile ("nop\n\t")
@@ -105,6 +167,7 @@
   // enable interrupts
   sei();
 }
+#endif	//	__SAM3X8E__
 #endif  // SOFTWARE_SPI
 //------------------------------------------------------------------------------
 // send command and return error code.  Return zero for OK
@@ -162,7 +225,9 @@
   }
 }
 //------------------------------------------------------------------------------
+#ifdef		USE_SPI_LIB		// 1YEN_201109: to suppress WARNING
 static uint8_t chip_select_asserted = 0;
+#endif
 
 void Sd2Card::chipSelectHigh(void) {
   digitalWrite(chipSelectPin_, HIGH);
@@ -258,6 +323,8 @@
   pinMode(SPI_MISO_PIN, INPUT);
   pinMode(SPI_MOSI_PIN, OUTPUT);
   pinMode(SPI_SCK_PIN, OUTPUT);
+// 1YEN_201109: to suppress WARNING
+sckRateID=sckRateID;
 #endif
 
 #ifndef SOFTWARE_SPI
@@ -510,6 +577,7 @@
     return false;
   }
 #ifndef USE_SPI_LIB
+#ifndef		__SAM3X8E__
   // see avr processor datasheet for SPI register bit definitions
   if ((sckRateID & 1) || sckRateID == 6) {
     SPSR &= ~(1 << SPI2X);
@@ -519,6 +587,7 @@
   SPCR &= ~((1 <<SPR1) | (1 << SPR0));
   SPCR |= (sckRateID & 4 ? (1 << SPR1) : 0)
     | (sckRateID & 2 ? (1 << SPR0) : 0);
+#endif	//	__SAM3X8E__
 #else // USE_SPI_LIB
   switch (sckRateID) {
     case 0:  settings = SPISettings(25000000, MSBFIRST, SPI_MODE0); break;
@@ -540,6 +609,14 @@
   settings = SPISettings(clock, MSBFIRST, SPI_MODE0);
   return true;
 }
+#else
+// 1YEN_201109:
+uint8_t		Sd2Card::setSpiClock (
+uint32_t	clock)
+{
+	clock=clock;
+	return (true);
+}
 #endif
 //------------------------------------------------------------------------------
 // wait for card to go not busy