Simon Ford / PCF8574

PCF8574 I2C IO Expander Interface

Dependents:   PCF8574_HelloWorld PCF8574_I2C_4x4_Keypad PCF8574_I2C_4x4_Keypad_interface PCF8574_ButtonPress

PCF8574.cpp@1:ec8da0c59403, 2010-06-03 (annotated)

Committer:
simon
Date:
Thu Jun 03 13:00:49 2010 +0000
Revision:
1:ec8da0c59403
Parent:
0:ab4e14b911ee 

        

        
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/* mbed PCF8574 Library, for driving the I2C I/O Expander





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 * Copyright (c) 2008-2010, cstyles, sford





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 *





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 * Permission is hereby granted, free of charge, to any person obtaining a copy





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 * of this software and associated documentation files (the "Software"), to deal





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 * in the Software without restriction, including without limitation the rights





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 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell





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 * copies of the Software, and to permit persons to whom the Software is





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 * furnished to do so, subject to the following conditions:





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 *





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 * The above copyright notice and this permission notice shall be included in





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 * all copies or substantial portions of the Software.





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 *





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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR





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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,





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 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE





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 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER





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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,





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 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN





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 * THE SOFTWARE.





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 */





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#include "PCF8574.h"





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#include "mbed.h"





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PCF8574::PCF8574(PinName sda, PinName scl, int address)





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        : _i2c(sda, scl) {





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    _address = address;





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}





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int PCF8574::read() {





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    char foo[1];





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    _i2c.read(_address, foo, 1);





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    return foo[0];





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}





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void PCF8574::write(int data) {





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    char foo[1];





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    foo[0] = data;





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    _i2c.write(_address, foo, 1);





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}