DigitalPin.h

Go to the documentation of this file.

/* Arduino DigitalIO Library
 * Copyright (C) 2013 by William Greiman
 *
 * This file is part of the Arduino DigitalIO Library
 *
 * This Library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This Library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with the Arduino DigitalIO Library.  If not, see
 * <http://www.gnu.org/licenses/>.
 */
#ifndef DigitalPin_h
#define DigitalPin_h
#if defined(__AVR__) || defined(DOXYGEN)
#include <avr/io.h>
struct GpioPinMap_t {
    volatile uint8_t* pin;   
    volatile uint8_t* ddr;   
    volatile uint8_t* port;  
    uint8_t mask;            
};
 
#define GPIO_PIN(reg, bit) {&PIN##reg, &DDR##reg, &PORT##reg, 1 << bit}
 
// Include pin map for current board.
#include "boards/GpioPinMap.h"
//------------------------------------------------------------------------------
void badPinNumber(void)
__attribute__((error("Pin number is too large or not a constant")));
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void badPinCheck(uint8_t pin)
{
    if (!__builtin_constant_p(pin) || pin >= NUM_DIGITAL_PINS) {
        badPinNumber();
    }
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
volatile uint8_t* ddrReg(uint8_t pin)
{
    badPinCheck(pin);
    return GpioPinMap[pin].ddr;
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
uint8_t pinMask(uint8_t pin)
{
    badPinCheck(pin);
    return GpioPinMap[pin].mask;
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
volatile uint8_t* pinReg(uint8_t pin)
{
    badPinCheck(pin);
    return GpioPinMap[pin].pin;
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
volatile uint8_t* portReg(uint8_t pin)
{
    badPinCheck(pin);
    return GpioPinMap[pin].port;
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastBitWriteSafe(volatile uint8_t* address, uint8_t mask, bool level)
{
    uint8_t s;
    if (address > reinterpret_cast<uint8_t*>(0X3F)) {
        s = SREG;
        cli();
    }
    if (level) {
        *address |= mask;
    } else {
        *address &= ~mask;
    }
    if (address > reinterpret_cast<uint8_t*>(0X3F)) {
        SREG = s;
    }
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
bool fastDigitalRead(uint8_t pin)
{
    return *pinReg(pin) & pinMask(pin);
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastDigitalToggle(uint8_t pin)
{
    if (pinReg(pin) > reinterpret_cast<uint8_t*>(0X3F)) {
        // must write bit to high address port
        *pinReg(pin) = pinMask(pin);
    } else {
        // will compile to sbi and PIN register will not be read.
        *pinReg(pin) |= pinMask(pin);
    }
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastDigitalWrite(uint8_t pin, bool level)
{
    fastBitWriteSafe(portReg(pin), pinMask(pin), level);
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastDdrWrite(uint8_t pin, bool level)
{
    fastBitWriteSafe(ddrReg(pin), pinMask(pin), level);
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastPinMode(uint8_t pin, uint8_t mode)
{
    fastDdrWrite(pin, mode == OUTPUT);
    if (mode != OUTPUT) {
        fastDigitalWrite(pin, mode == INPUT_PULLUP);
    }
}
#else  // defined(__AVR__)
#if defined(CORE_TEENSY)
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
bool fastDigitalRead(uint8_t pin)
{
    return *portInputRegister(pin);
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastDigitalWrite(uint8_t pin, bool value)
{
    if (value) {
        *portSetRegister(pin) = 1;
    } else {
        *portClearRegister(pin) = 1;
    }
}
#elif defined(__SAM3X8E__) || defined(__SAM3X8H__)
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
bool fastDigitalRead(uint8_t pin)
{
    return g_APinDescription[pin].pPort->PIO_PDSR & g_APinDescription[pin].ulPin;
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastDigitalWrite(uint8_t pin, bool value)
{
    if (value) {
        g_APinDescription[pin].pPort->PIO_SODR = g_APinDescription[pin].ulPin;
    } else {
        g_APinDescription[pin].pPort->PIO_CODR = g_APinDescription[pin].ulPin;
    }
}
#elif defined(ESP8266)
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
void fastDigitalWrite(uint8_t pin, uint8_t val)
{
    if (pin < 16) {
        if (val) {
            GPOS = (1 << pin);
        } else {
            GPOC = (1 << pin);
        }
    } else if (pin == 16) {
        if (val) {
            GP16O |= 1;
        } else {
            GP16O &= ~1;
        }
    }
}
//------------------------------------------------------------------------------
static inline __attribute__((always_inline))
bool fastDigitalRead(uint8_t pin)
{
    if (pin < 16) {
        return GPIP(pin);
    } else if (pin == 16) {
        return GP16I & 0x01;
    }
    return 0;
}
#else  // CORE_TEENSY
//------------------------------------------------------------------------------
inline void fastDigitalWrite(uint8_t pin, bool value)
{
    digitalWrite(pin, value);
}
//------------------------------------------------------------------------------
inline bool fastDigitalRead(uint8_t pin)
{
    return digitalRead(pin);
}
#endif  // CORE_TEENSY
//------------------------------------------------------------------------------
inline void fastDigitalToggle(uint8_t pin)
{
    fastDigitalWrite(pin, !fastDigitalRead(pin));
}
//------------------------------------------------------------------------------
inline void fastPinMode(uint8_t pin, uint8_t mode)
{
    pinMode(pin, mode);
}
#endif  // __AVR__
//------------------------------------------------------------------------------
#define fastPinConfig(pin, mode, level)\
    {fastPinMode(pin, mode); fastDigitalWrite(pin, level);}
//==============================================================================
template<uint8_t PinNumber>
class DigitalPin
{
public:
    //----------------------------------------------------------------------------
    DigitalPin() {}
    //----------------------------------------------------------------------------
    inline DigitalPin & operator = (bool value) __attribute__((always_inline))
    {
        write(value);
        return *this;
    }
    //----------------------------------------------------------------------------
    inline operator bool () const __attribute__((always_inline))
    {
        return read();
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    void config(uint8_t mode, bool level)
    {
        fastPinConfig(PinNumber, mode, level);
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    void high()
    {
        write(true);
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    void low()
    {
        write(false);
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    void mode(uint8_t mode)
    {
        fastPinMode(PinNumber, mode);
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    bool read() const
    {
        return fastDigitalRead(PinNumber);
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    void toggle()
    {
        fastDigitalToggle(PinNumber);
    }
    //----------------------------------------------------------------------------
    inline __attribute__((always_inline))
    void write(bool value)
    {
        fastDigitalWrite(PinNumber, value);
    }
};
#endif  // DigitalPin_h