Pixel Trinkey Analog JST pin (#369)

Adding analog support to the 3-pin JST A6.

Author: mikeysklar

variants/pixeltrinkey_m0/variant.cpp

@@ -33,8 +33,8 @@ const PinDescription g_APinDescription[]=
   { PORTA, 4, PIO_SERCOM_ALT, PIN_ATTR_DIGITAL, No_ADC_Channel, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_4 }, // D2 / MOSI
   { PORTA, 5, PIO_SERCOM_ALT, PIN_ATTR_DIGITAL, No_ADC_Channel, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_5 }, // D3 / SCK
 
-  // Extra Signal / MISO
-  { PORTA, 6, PIO_SERCOM_ALT, PIN_ATTR_DIGITAL, No_ADC_Channel, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_6 }, // D4 / MISO
+  // A6 / MISO
+  { PORTA, 6, PIO_ANALOG, PIN_ATTR_ANALOG, ADC_Channel6, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_NONE }, // A6 / MISO
 
   // USB pins D5, D6, D7
   { PORTA, 28, PIO_COM, PIN_ATTR_NONE, No_ADC_Channel, NOT_ON_PWM, NOT_ON_TIMER, EXTERNAL_INT_NONE }, // USB Host enable

variants/pixeltrinkey_m0/variant.h

@@ -89,8 +89,12 @@ extern "C"
 #define PIN_A0               (0ul)
 #define PIN_DAC0             PIN_A0
 
+#define PIN_A6               (4ul)
+
 static const uint8_t A0  = PIN_A0;
 
+static const uint8_t A6  = PIN_A6;
+
 #define ADC_RESOLUTION		12
 
 
@@ -99,7 +103,7 @@ static const uint8_t A0  = PIN_A0;
  */
 #define SPI_INTERFACES_COUNT 1
 
-#define PIN_SPI_MISO         (4ul) // not actually broken out
+#define PIN_SPI_MISO         (4ul) // off 3-pin JST, broken out
 #define PIN_SPI_MOSI         (2ul)
 #define PIN_SPI_SCK          (3ul)
 #define PERIPH_SPI           sercom0