PCF8575.cpp

00001 /* mbed PCF8574 Library, for driving the I2C I/O Expander
00002  * Copyright (c) 2008-2010, cstyles, sford (Originally PCF8574 lib)
00003  *                          new created by Lerche
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00020  * THE SOFTWARE.
00021  */
00022 
00023 #include "PCF8575.h"
00024 #include "mbed.h"
00025 
00026 PCF8575::PCF8575(PinName sda, PinName scl, int address)
00027         : _i2c(sda, scl) {
00028     _address = address;
00029 }
00030 
00031 int PCF8575::read() {
00032     char foo[2];
00033     _i2c.read(_address, foo, 2);
00034     
00035     return (foo[1] << 8) | foo[0];
00036 }
00037 
00038 void PCF8575::write(int data) {
00039     char foo[2];
00040     foo[0]=data;
00041     foo[1]=data>>8;
00042     _i2c.write(_address, foo, 2);
00043 }