mbed-os
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drivers/AnalogIn.h
- Committer:
- xuaner
- Date:
- 2017-07-20
- Revision:
- 1:3deb71413561
- Parent:
- 0:f269e3021894
File content as of revision 1:3deb71413561:
/* 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/platform.h" #if DEVICE_ANALOGIN #include "hal/analogin_api.h" #include "platform/SingletonPtr.h" #include "platform/PlatformMutex.h" namespace mbed { /** \addtogroup drivers */ /** @{*/ /** 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 BatteryLevel { public: BatteryLevel() { battery_init(&_adc); } unsigned short read_battery_u16() { unsigned short ret = battery_read_u16(&_adc); return ret; } virtual ~BatteryLevel() { // Do nothing } protected: analogin_t _adc; static SingletonPtr<PlatformMutex> _mutex; }; 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 /** @}*/