diff --git a/build/shared/revisions.txt b/build/shared/revisions.txt
index 4ff8faf0b..86801f1a8 100644
--- a/build/shared/revisions.txt
+++ b/build/shared/revisions.txt
@@ -12,6 +12,7 @@ ARDUINO 1.5.5 BETA
 
 [core]
 * sam: Fixed wrong initialization for ADC timings (analogRead speed Arduino DUE improved by a factor x10)
+       https://github.com/arduino/Arduino/issues/1418
        (http://www.djerickson.com/arduino/)
 * avr: Fixed wrong extended fuses on Arduino Yún when using external programmer
 * avr: Added yun variant with LED_BUILTIN definition
diff --git a/hardware/arduino/sam/system/libsam/source/adc.c b/hardware/arduino/sam/system/libsam/source/adc.c
index c4be3bb71..18a1b4c38 100644
--- a/hardware/arduino/sam/system/libsam/source/adc.c
+++ b/hardware/arduino/sam/system/libsam/source/adc.c
@@ -46,7 +46,7 @@ extern "C" {
  * @{
  */
 
-#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES || SAM3XA_SERIES
+#if SAM3S_SERIES || SAM4S_SERIES || SAM3N_SERIES
 /**
  * \brief Initialize the given ADC with the specified ADC clock and startup time.
  *
@@ -80,6 +80,55 @@ uint32_t adc_init(Adc *p_adc, const uint32_t ul_mck,
 			ADC_MR_STARTUP_Msk);
 	return 0;
 }
+#elif SAM3XA_SERIES
+/**
+ * \brief Initialize the given ADC with the specified ADC clock and startup time.
+ *
+ * \param p_adc Pointer to an ADC instance.
+ * \param ul_mck Main clock of the device (value in Hz).
+ * \param ul_adc_clock Analog-to-Digital conversion clock (value in Hz).
+ * \param uc_startup ADC start up time. Please refer to the product datasheet
+ * for details.
+ *
+ * \return 0 on success.
+ */
+uint32_t adc_init(Adc *p_adc, const uint32_t ul_mck,
+		const uint32_t ul_adc_clock, const uint8_t uc_startuptime)
+{
+	uint32_t startup_table[] = { 0, 8, 16, 24, 64, 80, 96, 112, 512, 576, 640, 704, 768, 832, 896, 960 };
+	uint32_t ul_prescal, ul_startup,  ul_mr_startup, ul_real_adc_clock;
+	p_adc->ADC_CR = ADC_CR_SWRST;
+
+	/* Reset Mode Register. */
+	p_adc->ADC_MR = 0;
+
+	/* Reset PDC transfer. */
+	p_adc->ADC_PTCR = (ADC_PTCR_RXTDIS | ADC_PTCR_TXTDIS);
+	p_adc->ADC_RCR = 0;
+	p_adc->ADC_RNCR = 0;
+	if (ul_mck % (2 * ul_adc_clock)) {
+		// Division with reminder
+		ul_prescal = ul_mck / (2 * ul_adc_clock);
+	} else {
+		// Whole division
+		ul_prescal = ul_mck / (2 * ul_adc_clock) - 1;
+	}
+	ul_real_adc_clock = ul_mck / (2 * (ul_prescal + 1));
+
+	// ADC clocks needed to get ul_startuptime uS
+	ul_startup = (ul_real_adc_clock / 1000000) * uc_startuptime;
+
+	// Find correct MR_STARTUP value from conversion table
+	for (ul_mr_startup=0; ul_mr_startup<16; ul_mr_startup++) {
+		if (startup_table[ul_mr_startup] >= ul_startup)
+			break;
+	}
+	if (ul_mr_startup==16)
+		return -1;
+	p_adc->ADC_MR |= ADC_MR_PRESCAL(ul_prescal) |
+			((ul_mr_startup << ADC_MR_STARTUP_Pos) & ADC_MR_STARTUP_Msk);
+	return 0;
+}
 #elif SAM3U_SERIES
 /**
  * \brief Initialize the given ADC with the specified ADC clock and startup time.
diff --git a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a
index c639827e3..7768e877c 100644
Binary files a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a and b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a differ
diff --git a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt
index ad730412f..cd1697e07 100644
--- a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt
+++ b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt
@@ -72,7 +72,7 @@ pmc.o:
 00000000 T pmc_switch_udpck_to_upllck
 
 pwmc.o:
-00000000 r C.18.4409
+00000000 r C.9.8049
 00000000 t FindClockConfiguration
 00000000 T PWMC_ConfigureChannel
 00000000 T PWMC_ConfigureChannelExt
@@ -100,14 +100,14 @@ pwmc.o:
 00000000 T PWMC_SetSyncChannelUpdateUnlock
 00000000 T PWMC_WriteBuffer
          U __assert_func
-00000000 r __func__.4405
-00000000 r __func__.4429
-00000000 r __func__.4463
-00000000 r __func__.4509
-00000000 r __func__.4542
-00000000 r __func__.4563
-00000000 r __func__.4712
-00000000 r __func__.4726
+00000000 r __func__.6631
+00000000 r __func__.6642
+00000000 r __func__.6657
+00000000 r __func__.6668
+00000000 r __func__.6679
+00000000 r __func__.6686
+00000000 r __func__.6770
+00000000 r __func__.6776
 
 rtc.o:
 00000000 T RTC_ClearSCCR
@@ -123,9 +123,9 @@ rtc.o:
 00000000 T RTC_SetTime
 00000000 T RTC_SetTimeAlarm
          U __assert_func
-00000000 r __func__.4402
-00000000 r __func__.4415
-00000000 r __func__.4423
+00000000 r __func__.6628
+00000000 r __func__.6637
+00000000 r __func__.6642
 
 rtt.o:
 00000000 T RTT_EnableIT
@@ -134,8 +134,8 @@ rtt.o:
 00000000 T RTT_SetAlarm
 00000000 T RTT_SetPrescaler
          U __assert_func
-00000000 r __func__.4412
-00000000 r __func__.4426
+00000000 r __func__.6635
+00000000 r __func__.6643
 
 spi.o:
 00000000 T SPI_Configure
@@ -161,9 +161,9 @@ tc.o:
 00000000 T TC_Start
 00000000 T TC_Stop
          U __assert_func
-00000000 r __func__.4404
-00000000 r __func__.4415
-00000000 r __func__.4425
+00000000 r __func__.6630
+00000000 r __func__.6636
+00000000 r __func__.6642
 
 timetick.o:
 00000000 T GetTickCount
@@ -190,18 +190,18 @@ twi.o:
 00000000 T TWI_TransferComplete
 00000000 T TWI_WriteByte
          U __assert_func
-00000000 r __func__.4770
-00000000 r __func__.4801
-00000000 r __func__.4814
-00000000 r __func__.4823
-00000000 r __func__.4845
-00000000 r __func__.4854
-00000000 r __func__.4865
-00000000 r __func__.4904
-00000000 r __func__.4914
-00000000 r __func__.4923
-00000000 r __func__.4931
-00000000 r __func__.4939
+00000000 r __func__.7003
+00000000 r __func__.7018
+00000000 r __func__.7022
+00000000 r __func__.7029
+00000000 r __func__.7033
+00000000 r __func__.7038
+00000000 r __func__.7046
+00000000 r __func__.7060
+00000000 r __func__.7065
+00000000 r __func__.7069
+00000000 r __func__.7074
+00000000 r __func__.7078
 
 usart.o:
 00000000 T USART_Configure
@@ -220,7 +220,7 @@ usart.o:
 00000000 T USART_Write
 00000000 T USART_WriteBuffer
          U __assert_func
-00000000 r __func__.4778
+00000000 r __func__.6924
 
 wdt.o:
 00000000 T WDT_Disable
@@ -298,6 +298,7 @@ startup_sam3xa.o:
          U main
 
 adc.o:
+00000000 r C.0.8141
 00000000 T adc_configure_power_save
 00000000 T adc_configure_sequence
 00000000 T adc_configure_timing
@@ -482,12 +483,12 @@ efc.o:
 00000000 T efc_get_wait_state
 00000000 T efc_init
 00000000 T efc_perform_command
-00000074 T efc_perform_fcr
+00000070 T efc_perform_fcr
 00000000 T efc_perform_read_sequence
 00000000 T efc_set_flash_access_mode
 00000000 T efc_set_wait_state
-00000070 T efc_write_fmr
-00000000 b iap_perform_command.4696
+0000006c T efc_write_fmr
+00000000 b iap_perform_command.6905
 
 gpbr.o:
 00000000 T gpbr_read
@@ -552,7 +553,6 @@ rstc.o:
 00000000 T rstc_start_software_reset
 
 emac.o:
-00000000 t T.43
 00000000 t circ_inc
 00000000 T emac_dev_get_tx_load
 00000000 T emac_dev_init
@@ -566,6 +566,7 @@ emac.o:
 00000000 T emac_phy_write
 00000000 t emac_reset_rx_mem
 00000000 t emac_reset_tx_mem
+00000000 t emac_wait_phy.clone.1
 00000000 b gs_rx_desc
 00000000 b gs_tx_callback
 00000000 b gs_tx_desc
diff --git a/hardware/arduino/sam/variants/arduino_due_x/variant.cpp b/hardware/arduino/sam/variants/arduino_due_x/variant.cpp
index fbf283fe0..ab43675ab 100644
--- a/hardware/arduino/sam/variants/arduino_due_x/variant.cpp
+++ b/hardware/arduino/sam/variants/arduino_due_x/variant.cpp
@@ -433,7 +433,7 @@ void init( void )
 
   // Initialize Analog Controller
   pmc_enable_periph_clk(ID_ADC);
-  adc_init(ADC, SystemCoreClock, ADC_FREQ_MAX, /*ADC_STARTUP_FAST*/ 3);
+  adc_init(ADC, SystemCoreClock, ADC_FREQ_MAX, ADC_STARTUP_FAST);
   adc_configure_timing(ADC, 0, ADC_SETTLING_TIME_3, 1);
   adc_configure_trigger(ADC, ADC_TRIG_SW, 0); // Disable hardware trigger.
   adc_disable_interrupt(ADC, 0xFFFFFFFF); // Disable all ADC interrupts.