File content as of revision 3:b902729a1675:

/* mbed simplified access to Microchip MCP23x17 GPIO expender devices (I2C)
 * Copyright (c) 2014-2015 ygarcia, MIT License
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software 
 * and associated documentation files (the "Software"), to deal in the Software without restriction, 
 * including without limitation the rights to use, copy, modify, merge, publish, distribute, 
 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is 
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or 
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING 
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#pragma once

#include <map>

#include "Debug.h"

#include "AbstractGpioExpender.h"

namespace MCP23017_I2C {
    /** This class provides simplified I2C access to a Microchip 2MCP28x17 GPIO expender. V0.0.0.1
     *
     * Note that if the LPC1768 is powered in 3.3V and Microchip MCP28x17 GPIO expender device could be powered at 3.3V or 5V.
     * In this case, you shall use a bi-directional level shifter for I2C-bus. Please refer to AN97055 (http://ics.nxp.com/support/documents/interface/pdf/an97055.pdf)
     * Microchip MCP28x17 GPIO expender device reference: DS21952B
     *
     * Note that for I2C details, please visit http://www.datelec.fr/fiches/I2C.htm
     *
     * Note that this header file include following headers:
     * - <string>
     * - <vector>
     * - <mbed.h>
     *
     * @author Yann Garcia (Don't hesitate to contact me: garcia.yann@gmail.com)
     */
    class CMCP23017_I2C : public AbstractGpioExpender {
        
        /** Reference counter used to guarentee unicity of the instance of I2C class
         */
        static unsigned char I2CModuleRefCounter;
        
        /** Device address input: A0, A1, A2 (Pins <1,3>). See DS21203K/DS21189D - Figure 5-1: Control Byte Format for address format details
         */
        unsigned char _slaveAddress;
        
        /** Interrupt on GPIOA
         */
        InterruptIn *_intA;
        
        /** Interrupt on GPIOB
         */
        InterruptIn *_intB;
        
        /** Device reset pin
         */
        DigitalOut *_reset;
        
        /** PortA config
         */
        unsigned char _gpioAFlags;
        
        /** PortB config
         */
        unsigned char _gpioBFlags;
        
        /** Map of declared buses
         */
        std::map<unsigned char, std::list<unsigned char> > _buses;
        
        /** Buses identifier index
         */
        unsigned char _busesIndex;
        
        /** An unique instance of I2C class
         */
        I2C *_i2cInstance;
        
    public:
        /** Constructor with Write Protect command pin wired. Use it to manage the first I2C module on 3.3V or 5V network
         *
         * @param p_sda: MBed pin for SDA
         * @param p_scl: MBed pin for SCL
         * @param p_address: Device address input: A0, A1, A2 (Pins <1,3>)
         * @param p_intA: MBed pin to manage interrupt on GPIOA, default value is NC, not connected
         * @param p_intB: MBed pin to manage device reset. If NC, WP is not managed, default value is NC, not connected
         * @param p_reset: MBed pin to manage Write Protect input. If NC, WP is not managed, default value is NC, not connected
         * @param p_internalPullUp: Set to true to use internal pull-up resistor, default value is true
         * @param p_frequency: Frequency of the I2C interface (SCL), default value is 400KHz
         * Example:
         * - If A1 and A2 pins are tired to Vdd and A0 is tired to Vss, address shall '00000110'B
         * - If A0 and A1 pins are tired to Vss and A2 is tired to Vdd, address shall '00000100'B
         */
        CMCP23017_I2C(const PinName p_sda, const PinName p_scl, const unsigned char p_address, const PinName p_intA = NC, const PinName p_intB = NC, const PinName p_reset = NC, const bool p_internalPullUp = true, const unsigned int p_frequency = 400000);
    
        /** Destructor
         */
        virtual ~CMCP23017_I2C();
        
        /** Initialize the module, configuring the module and starting the clock
         * @param p_gpioAFlags GPIO A port configuration: bit set for input mode, 0 for output mode. Default: ports as outputs
         * @param p_gpioBFlags GPIO B port configuration: bit set for input mode, 0 for output mode. Default: ports as outputs
         *
         * @return true on success, false otherwise
         */
        bool Initialize(const unsigned char p_gpioAFlags = 0x00, const unsigned char p_gpioBFlags = 0x00);

        /** Used to return the unique instance of I2C instance
         */
        inline const I2C * operator * () { return (const I2C *)_i2cInstance; };
        
        /** Reset the device
         */
        virtual void reset();
        
        /** Setup device interrupt mechanism
         * @param p_mirroring Set to 0x00 to disable INTA/B mirroring, 0x01 otherwise. Default: 0x00
         * @param p_openDrain Set to 0x00 for active driver output, 0x01 for opn drain output. Default: 0x00
         * @param p_polarity Set to 0x00 for interrupt active low, 0x01 otherwise. Default: 0x00
         */
        virtual void setupInterrupts(const unsigned char mirroring = 0x00, const unsigned char p_openDrain = 0x00, const unsigned char polarity = 0x00);
        
        /** Setup interrupt for a specific IO port
         * @param p_pinId The IO port identifier
         * @param p_mode  The interrupt mode
         * @return 0 on success, -1 on wrong parameters and -2 otherwise
         */
        virtual int setupInterruptPin(const unsigned char p_gpioId, const InterruptModes p_mode = OnRising);
        
        /** Setup pull mode for a specific IO port
         * @param p_gpioId The IO port identifier
         * @param p_mode  The interrupt mode
         * @return 0 on success, -1 on wrong parameters and -2 otherwise
         */
        virtual int setupPullPin(const unsigned char p_gpioId, const PullModes p_mode = PullOff);
        
        /** Get interrupt information and clear it
         * @param p_gpioId The IO port identifier where the interrupt occured
         * @param p_value  The logic value on the pin port where the interrupt occured
         * @return 0 on success, -1 on wrong parameters and -2 otherwise
         */
        virtual int getLastInterruptPinAndValue(unsigned char * p_gpioId, unsigned char * p_value);
        
        /** Read the specific GPIO port pin
         * @param p_gpioId The GPIO port pin to be read 
         * @param p_value The GPIO port pin value
         * @return 0 on success, -1 on wrong parameters and -2 otherwise
         */
            virtual int read(const unsigned char p_gpioId, unsigned char * p_value);
        
        /** Write value to the specific GPIO port pin
         * @param p_gpioId The GPIO port pin to be written
         * @param p_value The GPIO port pin value
         * @return 0 on success, -1 on wrong parameters and -2 otherwise
         */
        virtual int write(const unsigned char p_gpioId, const unsigned char p_value);
        
        virtual unsigned char createBus(const std::list<unsigned char> p_lines, const PinMode p_mode = PullNone);
        virtual void deleteBus(const unsigned char p_busId);
        virtual int busRead(const unsigned char p_busId, unsigned short * p_value);
        virtual int busWrite(const unsigned char p_busId, const unsigned short p_value);
        
        /** Attach a function to call when a interrupt occurs on the GPIOA input ports
         * @param p_fptr The pointer to the "C" callback function
         */
        virtual void setIntrACallback(void (* p_fptr)(void));
        
        /** Attach a function to call when a interrupt occurs on the GPIOB input ports
         * @param p_fptr The pointer to the "C" callback function
         */
        virtual void setIntrBCallback(void (* p_fptr)(void));
        
        /** Attach a member function to call when a interrupt occurs on the GPIOA input ports
         */
        template<typename T> 
        void setIntrACallback(const T * p_tptr, void(T::* p_mptr)(void));
        
        /** Attach a member function to call when a rising edge occurs on the input
         */
        template<typename T> 
        void setIntrBCallback(const T * p_tptr, void(T::* p_mptr)(void));
        
    private:
    
        /** Configure the device:
         *   BANK0 (A register followed by B register)
         *   INTs: active low
         *   INTs for all ports
         *   INTs are not mirrored
         * @param p_gpioAFlags GPIO A port configuration: bit set for input mode, 0 for output mode. Default: ports as outputs
         * @param p_gpioBFlags GPIO B port configuration: bit set for input mode, 0 for output mode. Default: ports as outputs
         */
        void configure(const unsigned char p_gpioAFlags, const unsigned char p_gpioBFlags);
        
        bool registerIdFromGpioId(const unsigned char p_gpioId, unsigned char * p_gpioRegisterId);
        
        inline unsigned char gpioBitFromGpioId(const unsigned char p_gpioId) {
            return static_cast<unsigned char>((p_gpioId < GPIO_MED) ? p_gpioId : (p_gpioId - GPIO_MED));
        };
        inline bool isBitSet(const unsigned char p_gpioRegisterValue, const unsigned char p_gpioBit) {
            return (bool)((unsigned char)(p_gpioRegisterValue >> p_gpioBit) == 0x01);
        };
        inline bool isBitEqual(const unsigned char p_gpioRegisterValue, const unsigned char p_gpioBit, const unsigned char p_value) {
            return (bool)((unsigned char)(p_gpioRegisterValue >> p_gpioBit) == (p_value & 0x01));
        };
        inline unsigned char setBit(unsigned char p_gpioRegisterValue, const unsigned char p_gpioBit, const unsigned char p_value) {
            return (p_gpioRegisterValue & ~(1 << p_gpioBit)) | ((p_value & 0x01) << p_gpioBit);
        };
        
    protected:
    
        /** Write value to a register
         * @param p_address The register address
         * @param p_byte The value to write to the register
         * @return 1 on success, false otherwise
         */
        virtual bool writeRegister(const unsigned char p_registerId, const unsigned char p_value);
        
        virtual bool readRegister(const unsigned char p_registerId, unsigned char * p_value);
        
    private:
        /** Internal reference identifier
         */
        std::string _internalId;

        void DumpRegisters();
        void DumpRegister(unsigned int p_registerId);
        
    }; // End of class CMCP23017_I2C

} // End of namespace _MCP23017_I2C

using namespace MCP23017_I2C;