mbed-os/drivers/BusOut.h

136 lines
4.1 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_BUSOUT_H
#define MBED_BUSOUT_H
#include "drivers/DigitalOut.h"
#include "platform/PlatformMutex.h"
#include "platform/NonCopyable.h"
namespace mbed {
/**
* \defgroup drivers_BusOut BusOut class
* \ingroup drivers-public-api-gpio
* @{
*/
/** A digital output bus, used for setting the state of a collection of pins
*/
class BusOut : private NonCopyable<BusOut> {
public:
/** Create an BusOut, connected to the specified pins
*
* @param p0 DigitalOut pin to connect to bus bit
* @param p1 DigitalOut pin to connect to bus bit
* @param p2 DigitalOut pin to connect to bus bit
* @param p3 DigitalOut pin to connect to bus bit
* @param p4 DigitalOut pin to connect to bus bit
* @param p5 DigitalOut pin to connect to bus bit
* @param p6 DigitalOut pin to connect to bus bit
* @param p7 DigitalOut pin to connect to bus bit
* @param p8 DigitalOut pin to connect to bus bit
* @param p9 DigitalOut pin to connect to bus bit
* @param p10 DigitalOut pin to connect to bus bit
* @param p11 DigitalOut pin to connect to bus bit
* @param p12 DigitalOut pin to connect to bus bit
* @param p13 DigitalOut pin to connect to bus bit
* @param p14 DigitalOut pin to connect to bus bit
* @param p15 DigitalOut pin to connect to bus bit
*
* @note Synchronization level: Thread safe
*
* @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)
*/
BusOut(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 BusOut, connected to the specified pins
*
* @param pins An array of pins to connect to bus the bit
*/
BusOut(PinName pins[16]);
virtual ~BusOut();
/** Write the value to the output bus
*
* @param value An integer specifying a bit to write for every corresponding DigitalOut pin
*/
void write(int value);
/** Read the value currently output on the bus
*
* @returns
* An integer with each bit corresponding to associated DigitalOut pin setting
*/
int read();
/** 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 write()
* \sa BusOut::write()
*/
BusOut &operator= (int v);
BusOut &operator= (BusOut &rhs);
/** Access to particular bit in random-iterator fashion
* @param index Bit Position
*/
DigitalOut &operator[](int index);
/** A shorthand for read()
* \sa BusOut::read()
*/
operator int();
#if !defined(DOXYGEN_ONLY)
protected:
virtual void lock();
virtual void unlock();
DigitalOut *_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;
#endif
};
/** @}*/
} // namespace mbed
#endif