Add function to select the measurement channel in continuous mode

2 files changed, 29 insertions, 2 deletions

diff --git a/src/devices/mode/continuous.rs b/src/devices/mode/continuous.rs
index 6bf5201..cd3edee 100644
--- a/src/devices/mode/continuous.rs
+++ b/src/devices/mode/continuous.rs
@@ -1,7 +1,8 @@
-//! Common functions
+//! Continuous measurement mode
 
 use core::marker::PhantomData;
-use { Ads1x1x, mode, Error, interface };
+use { Ads1x1x, conversion, Error, hal, interface, mode, Register };
+use channels::ChannelSelection;
 use super::super::OperatingMode;
 
 impl<DI, IC, CONV, E> Ads1x1x<DI, IC, CONV, mode::Continuous>
@@ -29,3 +30,19 @@ where
         Ok(())
     }
 }
+
+impl<DI, IC, CONV, E> Ads1x1x<DI, IC, CONV, mode::Continuous>
+where
+    DI: interface::ReadData<Error = E> + interface::WriteData<Error = E>,
+    CONV: conversion::ConvertMeasurement,
+{
+    /// Select the channel for measurements.
+    pub fn select_channel<CH>(&mut self, _channel: &mut CH) -> Result<(), Error<E>>
+    where
+        CH: hal::adc::Channel<Ads1x1x<DI, IC, CONV, mode::OneShot>, ID = ChannelSelection> {
+        let config = self.config.with_mux_bits(CH::channel());
+        self.iface.write_register(Register::CONFIG, config.bits)?;
+        self.config = config;
+        Ok(())
+    }
+}
diff --git a/tests/mux_i2c.rs b/tests/mux_i2c.rs
index ca10673..f448f04 100644
--- a/tests/mux_i2c.rs
+++ b/tests/mux_i2c.rs
@@ -49,6 +49,16 @@ macro_rules! mux_test {
                 assert_eq!(-2048, measurement);
                 destroy(dev);
             }
+
+            #[test]
+            fn continuous_can_select_channel() {
+                let config = Config::default().with_high($config_bits);
+                let transactions = [ I2cTrans::write(DEV_ADDR, vec![Register::CONFIG, config.msb(), config.lsb()]) ];
+                let dev = new(&transactions);
+                let mut dev = dev.into_continuous().unwrap();
+                dev.select_channel(&mut channel::$CS).unwrap();
+                destroy(dev);
+            }
         }
     };
 }