Add methods to measure voltage instead of raw value.

Author: reitermarkus

embedded-hal/src/adc.rs

@@ -50,6 +50,23 @@ pub trait AdcChannel: ErrorType {
     /// This should wait until data is ready and then read it.
     /// If the ADC's precision is less than 32 bits, the value must be scaled accordingly.
     fn read(&mut self) -> Result<u32, Self::Error>;
+
+    /// Take an measurement in millivolts.
+    fn measure_mv(&mut self) -> Result<i32, Self::Error> {
+      Ok(self.read()? as i32)
+    }
+
+    /// Take an measurement in microvolts.
+    fn measure_uv(&mut self) -> Result<i32, Self::Error> {
+      let uv = self.measure_mv()?;
+      Ok(uv.saturating_mul(1000))
+    }
+
+    /// Take an measurement in nanovolts.
+    fn measure_nv(&mut self) -> Result<i32, Self::Error> {
+      let uv = self.measure_uv()?;
+      Ok(uv.saturating_mul(1000))
+    }
 }
 
 impl<T> AdcChannel for &mut T