mbed-os/drivers/BusIn.h

137 lines
4.0 KiB
C++

/* mbed Microcontroller Library
* Copyright (c) 2006-2013 ARM Limited
* SPDX-License-Identifier: Apache-2.0
*
* 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"
#include "platform/NonCopyable.h"
namespace mbed {
/**
* \defgroup drivers_BusIn BusIn class
* \ingroup drivers-public-api-gpio
* @{
*/
/** A digital input bus, used for reading the state of a collection of pins
*
* @note Synchronization level: Thread safe
*/
class BusIn : private NonCopyable<BusIn> {
public:
/* Group: Configuration Methods */
/** Create an BusIn, connected to the specified pins
*
* @param p0 DigitalIn pin to connect to bus bit
* @param p1 DigitalIn pin to connect to bus bit
* @param p2 DigitalIn pin to connect to bus bit
* @param p3 DigitalIn pin to connect to bus bit
* @param p4 DigitalIn pin to connect to bus bit
* @param p5 DigitalIn pin to connect to bus bit
* @param p6 DigitalIn pin to connect to bus bit
* @param p7 DigitalIn pin to connect to bus bit
* @param p8 DigitalIn pin to connect to bus bit
* @param p9 DigitalIn pin to connect to bus bit
* @param p10 DigitalIn pin to connect to bus bit
* @param p11 DigitalIn pin to connect to bus bit
* @param p12 DigitalIn pin to connect to bus bit
* @param p13 DigitalIn pin to connect to bus bit
* @param p14 DigitalIn pin to connect to bus bit
* @param p15 DigitalIn pin to connect to bus bit
*
* @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);
/** Create an BusIn, connected to the specified pins
*
* @param pins An array of pins to connect to bus bit
*/
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 pull 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()
* \sa DigitalIn::read()
*/
operator int();
/** Access to particular bit in random-iterator fashion
* @param index Position of bit
*/
DigitalIn &operator[](int index);
#if !defined(DOXYGEN_ONLY)
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;
private:
virtual void lock();
virtual void unlock();
#endif
};
/** @}*/
} // namespace mbed
#endif