Diff: api/AnalogIn.h

Revision:

144:ef7eb2e8f9f7

Parent:

0:9b334a45a8ff

diff -r 423e1876dc07 -r ef7eb2e8f9f7 api/AnalogIn.h
--- a/api/AnalogIn.h	Tue Aug 02 14:07:36 2016 +0000
+++ b/api/AnalogIn.h	Fri Sep 02 15:07:44 2016 +0100
@@ -1,103 +1,128 @@
-/* mbed Microcontroller Library
- * Copyright (c) 2006-2013 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#ifndef MBED_ANALOGIN_H
-#define MBED_ANALOGIN_H
-
-#include "platform.h"
-
-#if DEVICE_ANALOGIN
-
-#include "analogin_api.h"
-
-namespace mbed {
-
-/** An analog input, used for reading the voltage on a pin
- *
- * Example:
- * @code
- * // Print messages when the AnalogIn is greater than 50%
- *
- * #include "mbed.h"
- *
- * AnalogIn temperature(p20);
- *
- * int main() {
- *     while(1) {
- *         if(temperature > 0.5) {
- *             printf("Too hot! (%f)", temperature.read());
- *         }
- *     }
- * }
- * @endcode
- */
-class AnalogIn {
-
-public:
-
-    /** Create an AnalogIn, connected to the specified pin
-     *
-     * @param pin AnalogIn pin to connect to
-     * @param name (optional) A string to identify the object
-     */
-    AnalogIn(PinName pin) {
-        analogin_init(&_adc, pin);
-    }
-
-    /** Read the input voltage, represented as a float in the range [0.0, 1.0]
-     *
-     * @returns A floating-point value representing the current input voltage, measured as a percentage
-     */
-    float read() {
-        return analogin_read(&_adc);
-    }
-
-    /** Read the input voltage, represented as an unsigned short in the range [0x0, 0xFFFF]
-     *
-     * @returns
-     *   16-bit unsigned short representing the current input voltage, normalised to a 16-bit value
-     */
-    unsigned short read_u16() {
-        return analogin_read_u16(&_adc);
-    }
-
-#ifdef MBED_OPERATORS
-    /** An operator shorthand for read()
-     *
-     * The float() operator can be used as a shorthand for read() to simplify common code sequences
-     *
-     * Example:
-     * @code
-     * float x = volume.read();
-     * float x = volume;
-     *
-     * if(volume.read() > 0.25) { ... }
-     * if(volume > 0.25) { ... }
-     * @endcode
-     */
-    operator float() {
-        return read();
-    }
-#endif
-
-protected:
-    analogin_t _adc;
-};
-
-} // namespace mbed
-
-#endif
-
-#endif
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef MBED_ANALOGIN_H
+#define MBED_ANALOGIN_H
+
+#include "platform.h"
+
+#if DEVICE_ANALOGIN
+
+#include "analogin_api.h"
+#include "SingletonPtr.h"
+#include "PlatformMutex.h"
+
+namespace mbed {
+
+/** An analog input, used for reading the voltage on a pin
+ *
+ * @Note Synchronization level: Thread safe
+ *
+ * Example:
+ * @code
+ * // Print messages when the AnalogIn is greater than 50%
+ *
+ * #include "mbed.h"
+ *
+ * AnalogIn temperature(p20);
+ *
+ * int main() {
+ *     while(1) {
+ *         if(temperature > 0.5) {
+ *             printf("Too hot! (%f)", temperature.read());
+ *         }
+ *     }
+ * }
+ * @endcode
+ */
+class AnalogIn {
+
+public:
+
+    /** Create an AnalogIn, connected to the specified pin
+     *
+     * @param pin AnalogIn pin to connect to
+     * @param name (optional) A string to identify the object
+     */
+    AnalogIn(PinName pin) {
+        lock();
+        analogin_init(&_adc, pin);
+        unlock();
+    }
+
+    /** Read the input voltage, represented as a float in the range [0.0, 1.0]
+     *
+     * @returns A floating-point value representing the current input voltage, measured as a percentage
+     */
+    float read() {
+        lock();
+        float ret = analogin_read(&_adc);
+        unlock();
+        return ret;
+    }
+
+    /** Read the input voltage, represented as an unsigned short in the range [0x0, 0xFFFF]
+     *
+     * @returns
+     *   16-bit unsigned short representing the current input voltage, normalised to a 16-bit value
+     */
+    unsigned short read_u16() {
+        lock();
+        unsigned short ret = analogin_read_u16(&_adc);
+        unlock();
+        return ret;
+    }
+
+    /** An operator shorthand for read()
+     *
+     * The float() operator can be used as a shorthand for read() to simplify common code sequences
+     *
+     * Example:
+     * @code
+     * float x = volume.read();
+     * float x = volume;
+     *
+     * if(volume.read() > 0.25) { ... }
+     * if(volume > 0.25) { ... }
+     * @endcode
+     */
+    operator float() {
+        // Underlying call is thread safe
+        return read();
+    }
+
+    virtual ~AnalogIn() {
+        // Do nothing
+    }
+
+protected:
+
+    virtual void lock() {
+        _mutex->lock();
+    }
+
+    virtual void unlock() {
+        _mutex->unlock();
+    }
+
+    analogin_t _adc;
+    static SingletonPtr<PlatformMutex> _mutex;
+};
+
+} // namespace mbed
+
+#endif
+
+#endif