diff --git a/variants/mkr1000/variant.cpp b/variants/mkr1000/variant.cpp
index 4a79a6a0aed9cd709aebf16a6b5e6da19c6021c3..932e94268e79b27bf809bf7ac5efbcd91c3309ed 100644
--- a/variants/mkr1000/variant.cpp
+++ b/variants/mkr1000/variant.cpp
@@ -67,7 +67,7 @@ const PinDescription g_APinDescription[] = {
  */
                                                                                                                                                // DIPO=3 DOPO=0
   { PORTA, 16, PIO_SERCOM,  (PIN_ATTR_DIGITAL|PIN_ATTR_PWM|PIN_ATTR_TIMER    ), No_ADC_Channel, PWM2_CH0,   TCC2_CH0,     EXTERNAL_INT_0    }, // MOSI: SERCOM1/PAD[0]
-  { PORTA, 17, PIO_SERCOM,  (PIN_ATTR_DIGITAL                                ), No_ADC_Channel, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_NONE }, // SCK:  SERCOM1/PAD[1]
+  { PORTA, 17, PIO_SERCOM,  (PIN_ATTR_DIGITAL                                ), No_ADC_Channel, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_1    }, // SCK:  SERCOM1/PAD[1]
   { PORTA, 19, PIO_SERCOM,  (PIN_ATTR_DIGITAL|PIN_ATTR_PWM|PIN_ATTR_TIMER    ), No_ADC_Channel, PWM3_CH1,   TC3_CH1,      EXTERNAL_INT_NONE }, // MISO: SERCOM1/PAD[3]
 
                                                                                                                                                // PINOUT=0