Add support for checking if alarms have matched and clearing the flag

README.md

@@ -19,6 +19,8 @@ This driver allows you to:
 - Select the function of the INT/SQW output pin. See `use_int_sqw_output_as_interrupt`.
 - Enable and disable the square-wave generation. See `enable_square_wave`.
 - Select the square-wave frequency. See `set_square_wave_frequency`.
+- Read whether alarms 1 or 2 have matched. See `has_alarm1_matched`.
+- Clear flag indicating that alarms 1 or 2 have matched. See `clear_alarm1_matched_flag`.
 - Enable and disable the 32kHz output when battery-powered. See `enable_32khz_output_on_battery`.
 - Set the temperature conversion rate. See `set_temperature_conversion_rate`.
 - Enable and disable the temperature conversions when battery-powered. See `enable_temperature_conversions_on_battery`.

src/ds323x/status.rs

@@ -40,11 +40,39 @@ where
         let status = self.status & !BitFlags::OSC_STOP;
         self.write_status_without_clearing_alarm(status)
     }
+
+    /// Read whether the Alarm1 has matched at some point.
+    ///
+    /// Once this is true, it will stay as such until cleared with
+    /// [`clear_alarm1_matched_flag()`](#method.clear_alarm1_matched_flag)
+    pub fn has_alarm1_matched(&mut self) -> Result<bool, Error<E>> {
         let status = self.iface.read_register(Register::STATUS)?;
-        if (status & BitFlags::OSC_STOP) != 0 {
-            self.iface.write_register(Register::STATUS, status & !BitFlags::OSC_STOP)?;
-        }
-        Ok(())
+        Ok((status & BitFlags::ALARM1F) != 0)
+    }
+
+    /// Clear flag signalling whether the Alarm1 has matched at some point.
+    ///
+    /// See also: [`has_alarm1_matched()`](#method.has_alarm1_matched)
+    pub fn clear_alarm1_matched_flag(&mut self) -> Result<(), Error<E>> {
+        let status = self.status | BitFlags::ALARM2F;
+        self.iface.write_register(Register::STATUS, status)
+    }
+
+    /// Read whether the Alarm2 has matched at some point.
+    ///
+    /// Once this is true, it will stay as such until cleared with
+    /// [`clear_alarm2_matched_flag()`](#method.clear_alarm2_matched_flag)
+    pub fn has_alarm2_matched(&mut self) -> Result<bool, Error<E>> {
+        let status = self.iface.read_register(Register::STATUS)?;
+        Ok((status & BitFlags::ALARM2F) != 0)
+    }
+
+    /// Clear flag signalling whether the Alarm2 has matched at some point.
+    ///
+    /// See also: [`has_alarm2_matched()`](#method.has_alarm2_matched)
+    pub fn clear_alarm2_matched_flag(&mut self) -> Result<(), Error<E>> {
+        let status = self.status | BitFlags::ALARM1F;
+        self.iface.write_register(Register::STATUS, status)
     }
 
     /// Read the temperature.

src/lib.rs

@@ -17,6 +17,8 @@
 //! - Select the function of the INT/SQW output pin. See [`use_int_sqw_output_as_interrupt`].
 //! - Enable and disable the square-wave generation. See [`enable_square_wave`].
 //! - Select the square-wave frequency. See [`set_square_wave_frequency`].
+//! - Read whether alarms 1 or 2 have matched. See [`has_alarm1_matched`].
+//! - Clear flag indicating that alarms 1 or 2 have matched. See [`clear_alarm1_matched_flag`].
 //! - Enable and disable the 32kHz output when battery powered. See [`enable_32khz_output_on_battery`].
 //! - Set the temperature conversion rate. See [`set_temperature_conversion_rate`].
 //! - Enable and disable the temperature conversions when battery-powered. See [`enable_temperature_conversions_on_battery`].
@@ -34,6 +36,8 @@
 //! [`use_int_sqw_output_as_interrupt`]: struct.Ds323x.html#method.use_int_sqw_output_as_interrupt
 //! [`enable_square_wave`]: struct.Ds323x.html#method.enable_square_wave
 //! [`set_square_wave_frequency`]: struct.Ds323x.html#method.set_square_wave_frequency
+//! [`has_alarm1_matched`]: struct.Ds323x.html#method.has_alarm1_matched
+//! [`clear_alarm1_matched_flag`]: struct.Ds323x.html#method.clear_alarm1_matched_flag
 //! [`enable_32khz_output_on_battery`]: struct.Ds323x.html#method.enable_32khz_output_on_battery
 //! [`set_temperature_conversion_rate`]: struct.Ds323x.html#method.set_temperature_conversion_rate
 //! [`enable_temperature_conversions_on_battery`]: struct.Ds323x.html#method.enable_temperature_conversions_on_battery

tests/configuration.rs

@@ -72,6 +72,15 @@ call_method_status_test!(en_32khz_out,  enable_32khz_output,
 call_method_status_test!(dis_32khz_out, disable_32khz_output,
     DS3231_POR_STATUS & !BF::EN32KHZ | BF::ALARM2F | BF::ALARM1F,
     DS323X_POR_STATUS & !BF::EN32KHZ | BF::ALARM2F | BF::ALARM1F);
+
+call_method_status_test!(clear_alarm1_matched,  clear_alarm1_matched_flag,
+    DS3231_POR_STATUS | BF::ALARM2F,
+    DS323X_POR_STATUS | BF::ALARM2F);
+
+call_method_status_test!(clear_alarm2_matched,  clear_alarm2_matched_flag,
+    DS3231_POR_STATUS | BF::ALARM1F,
+    DS323X_POR_STATUS | BF::ALARM1F);
+
 call_method_status_test!(clr_stop, clear_has_been_stopped_flag,
     DS3231_POR_STATUS & !BF::OSC_STOP | BF::ALARM2F | BF::ALARM1F,
     DS323X_POR_STATUS & !BF::OSC_STOP | BF::ALARM2F | BF::ALARM1F);

tests/status.rs

@@ -17,6 +17,12 @@ get_param_test!(is_not_busy, is_busy, STATUS, false, 0xFF & !BF::BUSY);
 get_param_test!(stopped,     has_been_stopped, STATUS, true,  0xFF);
 get_param_test!(not_stopped, has_been_stopped, STATUS, false, 0xFF & !BF::OSC_STOP);
 
+get_param_test!(alarm1_matched,     has_alarm1_matched, STATUS, true,  0xFF);
+get_param_test!(alarm1_not_matched, has_alarm1_matched, STATUS, false, 0xFF & !BF::ALARM1F);
+
+get_param_test!(alarm2_matched,     has_alarm2_matched, STATUS, true,  0xFF);
+get_param_test!(alarm2_not_matched, has_alarm2_matched, STATUS, false, 0xFF & !BF::ALARM2F);
+
 get_param_read_array_test!(temp_0,   get_temperature,    0.0,  TEMP_MSB, [0, 0], [0, 0]);
 get_param_read_array_test!(temp_min, get_temperature, -128.0,  TEMP_MSB, [0b1000_0000, 0], [0, 0]);
 get_param_read_array_test!(temp_max, get_temperature,  127.75, TEMP_MSB, [0b0111_1111, 0b1100_0000], [0, 0]);