wire.h

00001 
00002 /*
00003 
00004     Copyright (c) 2014 RedBearLab, All rights reserved.
00005 
00006     This library is free software; you can redistribute it and/or
00007     modify it under the terms of the GNU Lesser General Public
00008     License as published by the Free Software Foundation; either
00009     version 2.1 of the License, or (at your option) any later version.
00010 
00011     This library is distributed in the hope that it will be useful,
00012     but WITHOUT ANY WARRANTY; without even the implied warranty of
00013     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
00014     See the GNU Lesser General Public License for more details.
00015 
00016     You should have received a copy of the GNU Lesser General Public
00017     License along with this library; if not, write to the Free Software
00018     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00019 
00020     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00021     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00022     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00023     IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
00024     CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
00025     TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
00026     SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00027 
00028 */
00029 
00030 #ifndef _WIRE_H_
00031 #define _WIRE_H_
00032 
00033 #include "mbed.h"
00034 
00035 #define TWI_DELAY(x)                    wait_us(x);
00036 
00037 #define BUFF_MAX_LENGTH                 128
00038 
00039 #define MAX_TIMEOUT_LOOPS               (20000UL)
00040 
00041 #define TWI_FREQUENCY_100K              0 
00042 #define TWI_FREQUENCY_250K              1 
00043 #define TWI_FREQUENCY_400K              2 
00044 
00045 #define TWI_SCL                         28
00046 #define TWI_SDA                         29
00047 
00048 
00049 class TwoWire
00050 {  
00051     public :
00052         TwoWire(NRF_TWI_Type *twi_use);
00053         void begin();
00054         void begin(uint32_t scl_pin, uint32_t sda_pin, uint8_t speed);
00055         void beginTransmission(uint8_t);
00056         void beginTransmission(int);
00057         uint8_t endTransmission(void);
00058         uint8_t endTransmission(uint8_t);
00059         uint8_t requestFrom(uint8_t, uint8_t);
00060         uint8_t requestFrom(uint8_t, uint8_t, uint8_t);
00061         uint8_t requestFrom(int, int);
00062         uint8_t requestFrom(int, int, int);
00063         int write(uint8_t);
00064         int write(const uint8_t *, size_t);
00065         int available(void);
00066         int read(void);  
00067         
00068      private : 
00069         uint8_t RX_Buffer[BUFF_MAX_LENGTH];
00070         uint8_t RX_BufferIndex;
00071         uint8_t RX_BufferLength;
00072         
00073         uint8_t TX_Buffer[BUFF_MAX_LENGTH];
00074         uint8_t TX_BufferIndex;
00075         uint8_t TX_BufferLength;
00076         
00077         NRF_TWI_Type *twi;
00078         
00079         uint8_t PPI_channel;
00080         uint8_t Transform_Addr;
00081         
00082         uint32_t SDA_Pin;
00083         uint32_t SCL_Pin;
00084         
00085         uint32_t twi_frequency;
00086 
00087         enum TwoWireStatus {
00088             UNINITIALIZED,
00089             MASTER_IDLE,
00090             MASTER_SEND,
00091             MASTER_RECV,
00092             SLAVE_IDLE,
00093             SLAVE_RECV,
00094             SLAVE_SEND
00095         };
00096         TwoWireStatus twi_status;
00097         
00098         bool twi_master_clear_bus(void);
00099         bool twi_master_init(void);
00100         uint8_t twi_master_read(uint8_t *data, uint8_t data_length, uint8_t issue_stop_condition);
00101         uint8_t twi_master_write(uint8_t *data, uint8_t data_length, uint8_t issue_stop_condition);
00102 };
00103 
00104 #endif