mbed-os/drivers/BusInOut.h

145 lines
4.3 KiB
C++

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