SakuraIO_I2C.cpp

00001 /* SAKURA Internet IoT Communication Module Library for mbed
00002  * 
00003  * The MIT License (MIT)
00004  * 
00005  * Copyright (c) SAKURA Internet Inc.
00006  * 
00007  * Permission is hereby granted, free of charge, to any person obtaining a copy
00008  * of this software and associated documentation files (the "Software"),
00009  * to deal in the Software without restriction, including without limitation
00010  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
00011  * and/or sell copies of the Software, and to permit persons to whom the Software
00012  * is furnished to do so, subject to the following conditions:
00013  * 
00014  * The above copyright notice and this permission notice shall be included
00015  * in all copies or substantial portions of the Software.
00016  * 
00017  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00018  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00019  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00020  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00021  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
00022  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00023  */
00024 
00025 #include "mbed.h"
00026 #include "SakuraIO.h"
00027 #include "debug.h"
00028  
00029 #define SAKURAIO_SLAVE_ADDR 0x4F
00030  
00031 #define MODE_IDLE  0x00
00032 #define MODE_WRITE 0x01
00033 #define MODE_READ  0x02
00034  
00035 void SakuraIO_I2C::begin(){
00036   mode = MODE_IDLE;
00037 }
00038  
00039 void SakuraIO_I2C::end(){
00040   switch(mode){
00041     case MODE_WRITE:
00042       i2c.stop();
00043       break;
00044     case MODE_READ:
00045       while (_length > 0) {
00046         _length --;
00047         i2c.read(_length > 0 ? 1 : 0);
00048       }
00049       i2c.stop();
00050       break;
00051   }
00052  
00053   mode = MODE_IDLE;
00054 }
00055  
00056 void SakuraIO_I2C::sendByte(uint8_t data){
00057   if(mode != MODE_WRITE){
00058     dbg("beginTr\r\n");
00059     i2c.start();
00060     i2c.write(SAKURAIO_SLAVE_ADDR<<1);
00061     mode = MODE_WRITE;
00062   }
00063   dbg("Write=%02x\r\n", data);
00064   i2c.write(data);
00065 }
00066  
00067  
00068 uint8_t SakuraIO_I2C::startReceive(uint8_t length){
00069   if(mode != MODE_IDLE){
00070     dbg("endTransmission\r\n");
00071     i2c.stop();
00072   }
00073   dbg("requestForm=%d\r\n", length);
00074   _length = length;
00075   i2c.start();
00076   i2c.write(SAKURAIO_SLAVE_ADDR<<1 | 1);
00077   mode = MODE_READ;
00078   return 0;
00079 }
00080  
00081 uint8_t SakuraIO_I2C::receiveByte(){
00082   return receiveByte(false);
00083 }
00084  
00085 uint8_t SakuraIO_I2C::receiveByte(bool stop){
00086   uint8_t ret = 0;
00087   if (_length > 0) {
00088     _length --;
00089     ret = i2c.read(_length > 0 ? 1 : 0);
00090   }
00091   if(stop){
00092     end();
00093   }
00094   dbg("Read=%d\r\n", ret);
00095   return ret;
00096 }
00097  
00098 SakuraIO_I2C::SakuraIO_I2C (I2C &_i2c) : i2c(_i2c) {
00099   mode = MODE_IDLE;
00100 }
00101  
00102 SakuraIO_I2C::SakuraIO_I2C (PinName sda, PinName scl) : i2c(sda, scl) {
00103   mode = MODE_IDLE;
00104 }