1 files changed, 86 insertions, 0 deletions
diff --git a/src/channels.rs b/src/channels.rs
new file mode 100644
index 0000000..c202ad3
--- /dev/null
+++ b/src/channels.rs
@@ -0,0 +1,86 @@
+//! ADC input channels
+use { Ads1x1x, ic, hal, Config, BitFlags as BF };
+
+/// ADC input channel selection
+#[allow(dead_code)]
+pub mod channel {
+    /// Measure single-ended signal on input channel 0
+    pub struct SingleA0;
+    /// Measure single-ended signal on input channel 1
+    pub struct SingleA1;
+    /// Measure single-ended signal on input channel 2
+    pub struct SingleA2;
+    /// Measure single-ended signal on input channel 3
+    pub struct SingleA3;
+    /// Measure signal on input channel 0 differentially to signal on input channel 1
+    pub struct DifferentialA0A1;
+    /// Measure signal on input channel 0 differentially to signal on input channel 3
+    pub struct DifferentialA0A3;
+    /// Measure signal on input channel 1 differentially to signal on input channel 3
+    pub struct DifferentialA1A3;
+    /// Measure signal on input channel 3 differentially to signal on input channel 3
+    pub struct DifferentialA2A3;
+}
+
+pub enum ChannelSelection {
+    SingleA0,
+    SingleA1,
+    SingleA2,
+    SingleA3,
+    DifferentialA0A1,
+    DifferentialA0A3,
+    DifferentialA1A3,
+    DifferentialA2A3,
+}
+
+macro_rules! impl_channel {
+    ( $IC:ident, $CH:ident ) => {
+        impl<DI, MODE> hal::adc::Channel<Ads1x1x<DI, ic::$IC, MODE>> for channel::$CH {
+            type ID = ChannelSelection;
+
+            fn channel() -> Self::ID {
+                ChannelSelection::$CH
+            }
+        }
+    }
+}
+
+impl_channel!(Ads1013, DifferentialA0A1);
+impl_channel!(Ads1113, DifferentialA0A1);
+
+impl_channel!(Ads1014, DifferentialA0A1);
+impl_channel!(Ads1114, DifferentialA0A1);
+
+impl_channel!(Ads1015, DifferentialA0A1);
+impl_channel!(Ads1015, DifferentialA0A3);
+impl_channel!(Ads1015, DifferentialA1A3);
+impl_channel!(Ads1015, DifferentialA2A3);
+impl_channel!(Ads1015, SingleA0);
+impl_channel!(Ads1015, SingleA1);
+impl_channel!(Ads1015, SingleA2);
+impl_channel!(Ads1015, SingleA3);
+
+impl_channel!(Ads1115, DifferentialA0A1);
+impl_channel!(Ads1115, DifferentialA0A3);
+impl_channel!(Ads1115, DifferentialA1A3);
+impl_channel!(Ads1115, DifferentialA2A3);
+impl_channel!(Ads1115, SingleA0);
+impl_channel!(Ads1115, SingleA1);
+impl_channel!(Ads1115, SingleA2);
+impl_channel!(Ads1115, SingleA3);
+
+impl Config {
+    pub(crate) fn with_mux_bits(&self, ch: ChannelSelection) -> Self {
+        use self::ChannelSelection as CS;
+        match ch {
+            CS::DifferentialA0A1 => self.with_low( BF::MUX2).with_low( BF::MUX1).with_low( BF::MUX0),
+            CS::DifferentialA0A3 => self.with_low( BF::MUX2).with_low( BF::MUX1).with_high(BF::MUX0),
+            CS::DifferentialA1A3 => self.with_low( BF::MUX2).with_high(BF::MUX1).with_low( BF::MUX0),
+            CS::DifferentialA2A3 => self.with_low( BF::MUX2).with_high(BF::MUX1).with_high(BF::MUX0),
+            CS::SingleA0         => self.with_high(BF::MUX2).with_low( BF::MUX1).with_low( BF::MUX0),
+            CS::SingleA1         => self.with_high(BF::MUX2).with_low( BF::MUX1).with_high(BF::MUX0),
+            CS::SingleA2         => self.with_high(BF::MUX2).with_high(BF::MUX1).with_low( BF::MUX0),
+            CS::SingleA3         => self.with_high(BF::MUX2).with_high(BF::MUX1).with_high(BF::MUX0),
+        }
+    }
+}