MKR1010 ADC Muxing

Official Hardware MKR Family MKR WiFi 1010
1

I'm trying to read 8 analog inputs on a MKR1010. I'm trying to mux pin D2 (PA10) to the ADC. This seems to be allowed by the pin description array. Note that Port A, 10 has an option for ADC_Channel18:

const PinDescription g_APinDescription[] = {

/*
 +------------+------------------+--------+-----------------+--------+-----------------------+---------+---------+--------+--------+----------+----------+
 | Pin number |  MKR  Board pin  |  PIN   | Notes           | Peri.A |     Peripheral B      | Perip.C | Perip.D | Peri.E | Peri.F | Periph.G | Periph.H |
 |            |                  |        |                 |   EIC  | ADC |  AC | PTC | DAC | SERCOMx | SERCOMx |  TCCx  |  TCCx  |    COM   | AC/GLCK  |
 |            |                  |        |                 |(EXTINT)|(AIN)|(AIN)|     |     | (x/PAD) | (x/PAD) | (x/WO) | (x/WO) |          |          |
 +------------+------------------+--------+-----------------+--------+-----+-----+-----+-----+---------+---------+--------+--------+----------+----------+
 | 00         | D0               |  PA22  |                 |  *06   |     |     | X10 |     |   3/00  |   5/00  |* TC4/0 | TCC0/4 |          | GCLK_IO6 |
 | 01         | D1               |  PA23  |                 |  *07   |     |     | X11 |     |   3/01  |   5/01  |* TC4/1 | TCC0/5 | USB/SOF  | GCLK_IO7 |
 | 02         | D2               |  PA10  |                 |   10   | *18 |     | X02 |     |   0/02  |   2/02  |*TCC1/0 | TCC0/2 | I2S/SCK0 | GCLK_IO4 |
 | 03         | D3               |  PA11  |                 |   11   | *19 |     | X03 |     |   0/03  |   2/03  |*TCC1/1 | TCC0/3 | I2S/FS0  | GCLK_IO5 |
 | 04         | D4               |  PB10  |                 |  *10   |     |     |     |     |         |   4/02  |* TC5/0 | TCC0/4 | I2S/MCK1 | GCLK_IO4 |
 | 05         | D5               |  PB11  |                 |  *11   |     |     |     |     |         |   4/03  |* TC5/1 | TCC0/5 | I2S/SCK1 | GCLK_IO5 |
 | 06         | D6               |  PA20  | LED_BUILTIN     |  *04   |     |     | X08 |     |   5/02  |   3/02  |        |*TCC0/6 | I2S/SCK0 | GCLK_IO4 |
 | 07         | D7               |  PA21  |                 |  *05   |     |     | X09 |     |   5/03  |   3/03  |        |*TCC0/7 | I2S/FS0  | GCLK_IO5 |
 +------------+------------------+--------+-----------------+--------+-----+-----+-----+-----+---------+---------+--------+--------+----------+----------+
 */
  { PORTA, 22, PIO_DIGITAL, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM|PIN_ATTR_TIMER    ), No_ADC_Channel, PWM4_CH0,   TC4_CH0,      EXTERNAL_INT_6    },
  { PORTA, 23, PIO_DIGITAL, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM|PIN_ATTR_TIMER    ), No_ADC_Channel, PWM4_CH1,   TC4_CH1,      EXTERNAL_INT_7    },
  { PORTA, 10, PIO_DIGITAL, (PIN_ATTR_DIGITAL|PIN_ATTR_PWM|PIN_ATTR_TIMER    ), ADC_Channel18,  PWM1_CH0,   TCC1_CH0,     EXTERNAL_INT_NONE },

pinRead() however, has this line which seems to prevent using pins that are before the ADC pins in the pin description array as ADC:

int analogRead(pin_size_t pin)
{
  uint32_t valueRead = 0;

  if (pin < A0) {
    pin += A0;
  }

Is there a workaround for this? Rewrite analogRead for just the D2 pin? Many thanks.

2

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