SRF08.h

00001 /*
00002 Copyright (c) 2012 Brent Dekker
00003  
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 #ifndef SRF08_H
00024 #define SRF08_H
00025  
00026 #include "mbed.h"
00027 #include "rtos.h"
00028  
00029 /**
00030  * The SRF08 is an ultrasonic range finder with an I2C interface that allows 
00031  * the measurement to be read directly in centimetres. More information can be
00032  * found on this website: http://www.robot-electronics.co.uk/htm/srf08tech.shtml
00033  */
00034 class SRF08 {
00035  
00036 public:
00037  
00038     /**
00039      * Create a SRF08 object connected to the specified I2C pins and address
00040      *
00041      * @param SDA I2C SDA pin to connect to
00042      * @param SCL I2C SCL pin to connect to
00043      * @param i2cAddress Address of WSRF08 on I2C bus
00044      */
00045     SRF08(PinName SDA, PinName SCL, int i2cAddress);
00046     
00047     /**
00048      * Send the "Start ranging in cm" command via I2C
00049      */
00050     void startRanging();
00051     
00052     /**
00053      * Checks if the module has finished ranging
00054      *
00055      * @param returns Boolean stating module is finished or not
00056      */
00057     bool rangingFinished();
00058     
00059     /**
00060      * Gets the measured range from the module
00061      *
00062      * @param returns Integer range in centimetre
00063      */
00064     int getRange();
00065     
00066     /**
00067      * Gets the measured light intensity from the module
00068      *
00069      * @param returns A normalised number 0-255 representing dark to light
00070      */
00071      int getLightIntensity();
00072      
00073     /**
00074      * Sets the range register of the SRF08 for faster ranging.
00075      * 
00076      * The max range is ((rangeVal x 43mm) + 43mm). The sensors maximum range
00077      *  is about six metres
00078      *
00079      * @param rangeVal The value written to the range register of the SRF08
00080      */
00081     void setRangeRegister(unsigned char rangeVal);
00082      
00083     /**
00084      * Sets the max gain register of the SRF08.
00085      * 
00086      * @param gainVal The value written to the max gain register of the SRF08
00087      */
00088     void setMaxGainRegister(unsigned char gainVal);
00089     
00090     /**
00091      * Changes the I2C address of the SRF08.
00092      *
00093      * The factory default address is 0x0E (224)
00094      *  The address can have the following values:
00095      *   E0 | E2 | E4 | E6 ... FC | FE
00096      * 
00097      * @param i2cAddress The new I2C address for the SRF08. 
00098      */
00099     void setAddress(int i2cAddress);
00100      
00101 protected:
00102  
00103     I2C i2cMod;
00104     unsigned char i2cAddress;
00105     bool rangingBusy;
00106     
00107     void setRangingFinished();
00108 };
00109  
00110 #endif