/// Reference source for ADC conversion
#[repr(u8)]
pub enum RefSource {
    /// External reference
    External = 0b00,
    /// Internal 2.5V reference
    Internal = 0b10,
    /// AVDD1 − AVSS
    Avdd1MinusAvss = 0b11,
    Invalid = 0b01,
}

impl From<u8> for RefSource {
    fn from(x: u8) -> Self {
        match x {
            0 => RefSource::External,
            1 => RefSource::Internal,
            2 => RefSource::Avdd1MinusAvss,
            _ => RefSource::Invalid,
        }
    }
}