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Diff: drivers/BusIn.h
- Revision:
- 149:156823d33999
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/drivers/BusIn.h Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,108 @@ +/* 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_BUSIN_H +#define MBED_BUSIN_H + +#include "platform/platform.h" +#include "drivers/DigitalIn.h" +#include "platform/PlatformMutex.h" + +namespace mbed { +/** \addtogroup drivers */ +/** @{*/ + +/** A digital input bus, used for reading the state of a collection of pins + * + * @Note Synchronization level: Thread safe + */ +class BusIn { + +public: + /* Group: Configuration Methods */ + + /** Create an BusIn, connected to the specified pins + * + * @param <n> DigitalIn pin to connect to bus bit <n> (p5-p30, NC) + * + * @note + * It is only required to specify as many pin variables as is required + * for the bus; the rest will default to NC (not connected) + */ + BusIn(PinName p0, PinName p1 = NC, PinName p2 = NC, PinName p3 = NC, + PinName p4 = NC, PinName p5 = NC, PinName p6 = NC, PinName p7 = NC, + PinName p8 = NC, PinName p9 = NC, PinName p10 = NC, PinName p11 = NC, + PinName p12 = NC, PinName p13 = NC, PinName p14 = NC, PinName p15 = NC); + + BusIn(PinName pins[16]); + + virtual ~BusIn(); + + /** Read the value of the input bus + * + * @returns + * An integer with each bit corresponding to the value read from the associated DigitalIn pin + */ + int read(); + + /** Set the input pin mode + * + * @param mode PullUp, PullDown, PullNone + */ + void mode(PinMode pull); + + /** Binary mask of bus pins connected to actual pins (not NC pins) + * If bus pin is in NC state make corresponding bit will be cleared (set to 0), else bit will be set to 1 + * + * @returns + * Binary mask of connected pins + */ + int mask() { + // No lock needed since _nc_mask is not modified outside the constructor + return _nc_mask; + } + + /** A shorthand for read() + */ + operator int(); + + /** Access to particular bit in random-iterator fashion + */ + DigitalIn & operator[] (int index); + +protected: + DigitalIn* _pin[16]; + + /** Mask of bus's NC pins + * If bit[n] is set to 1 - pin is connected + * if bit[n] is cleared - pin is not connected (NC) + */ + int _nc_mask; + + PlatformMutex _mutex; + + /* disallow copy constructor and assignment operators */ +private: + virtual void lock(); + virtual void unlock(); + BusIn(const BusIn&); + BusIn & operator = (const BusIn&); +}; + +} // namespace mbed + +#endif + +/** @}*/