File content as of revision 24:baa43caa2f3d:

/*

    Copyright (c) 2014 RedBearLab, All rights reserved.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 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 Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    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.

*/

#ifndef _WIRE_H_
#define _WIRE_H_

#include "mbed.h"

#define TWI_DELAY(x)                    wait_us(x);

#define BUFF_MAX_LENGTH                 128

#define MAX_TIMEOUT_LOOPS               (20000UL)

#define TWI_FREQUENCY_100K              0 
#define TWI_FREQUENCY_250K              1 
#define TWI_FREQUENCY_400K              2 

#define TWI_SCL                         28
#define TWI_SDA                         29


class TwoWire
{  
    public :
        TwoWire(NRF_TWI_Type *twi_use);
        void begin();
        void begin(uint32_t scl_pin, uint32_t sda_pin, uint8_t speed);
        void beginTransmission(uint8_t);
        void beginTransmission(int);
        uint8_t endTransmission(void);
        uint8_t endTransmission(uint8_t);
        uint8_t requestFrom(uint8_t, uint8_t);
        uint8_t requestFrom(uint8_t, uint8_t, uint8_t);
        uint8_t requestFrom(int, int);
        uint8_t requestFrom(int, int, int);
        int write(uint8_t);
        int write(const uint8_t *, size_t);
        int available(void);
        int read(void);  
        
     private : 
        uint8_t RX_Buffer[BUFF_MAX_LENGTH];
        uint8_t RX_BufferIndex;
        uint8_t RX_BufferLength;
        
        uint8_t TX_Buffer[BUFF_MAX_LENGTH];
        uint8_t TX_BufferIndex;
        uint8_t TX_BufferLength;
        
        NRF_TWI_Type *twi;
        
        uint8_t PPI_channel;
        uint8_t Transform_Addr;
        
        uint32_t SDA_Pin;
        uint32_t SCL_Pin;
        
        uint32_t twi_frequency;

        enum TwoWireStatus {
            UNINITIALIZED,
            MASTER_IDLE,
            MASTER_SEND,
            MASTER_RECV,
            SLAVE_IDLE,
            SLAVE_RECV,
            SLAVE_SEND
        };
        TwoWireStatus twi_status;
        
        bool twi_master_clear_bus(void);
        bool twi_master_init(void);
        uint8_t twi_master_read(uint8_t *data, uint8_t data_length, uint8_t issue_stop_condition);
        uint8_t twi_master_write(uint8_t *data, uint8_t data_length, uint8_t issue_stop_condition);
};

#endif