mbed library sources
Fork of mbed-src by
api/AnalogOut.h
- Committer:
- mbed_official
- Date:
- 2015-09-30
- Revision:
- 636:a11c0372f0ba
- Parent:
- 13:0645d8841f51
File content as of revision 636:a11c0372f0ba:
/* 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_ANALOGOUT_H #define MBED_ANALOGOUT_H #include "platform.h" #if DEVICE_ANALOGOUT #include "analogout_api.h" namespace mbed { /** An analog output, used for setting the voltage on a pin * * Example: * @code * // Make a sawtooth output * * #include "mbed.h" * * AnalogOut tri(p18); * int main() { * while(1) { * tri = tri + 0.01; * wait_us(1); * if(tri == 1) { * tri = 0; * } * } * } * @endcode */ class AnalogOut { public: /** Create an AnalogOut connected to the specified pin * * @param AnalogOut pin to connect to (18) */ AnalogOut(PinName pin) { analogout_init(&_dac, pin); } /** Set the output voltage, specified as a percentage (float) * * @param value A floating-point value representing the output voltage, * specified as a percentage. The value should lie between * 0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%). * Values outside this range will be saturated to 0.0f or 1.0f. */ void write(float value) { analogout_write(&_dac, value); } /** Set the output voltage, represented as an unsigned short in the range [0x0, 0xFFFF] * * @param value 16-bit unsigned short representing the output voltage, * normalised to a 16-bit value (0x0000 = 0v, 0xFFFF = 3.3v) */ void write_u16(unsigned short value) { analogout_write_u16(&_dac, value); } /** Return the current output voltage setting, measured as a percentage (float) * * @returns * A floating-point value representing the current voltage being output on the pin, * measured as a percentage. The returned value will lie between * 0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%). * * @note * This value may not match exactly the value set by a previous write(). */ float read() { return analogout_read(&_dac); } #ifdef MBED_OPERATORS /** An operator shorthand for write() */ AnalogOut& operator= (float percent) { write(percent); return *this; } AnalogOut& operator= (AnalogOut& rhs) { write(rhs.read()); return *this; } /** An operator shorthand for read() */ operator float() { return read(); } #endif protected: dac_t _dac; }; } // namespace mbed #endif #endif