HMC6352.h

00001 // Copyright 2009 Richard Parker
00002 
00003 #ifndef MBED_HMC6352_H
00004 #define MBED_HMC6352_H
00005 
00006 #include "mbed.h"
00007 
00008 class HMC6352
00009 {
00010 public:
00011     // Enum to make the returned mode more readable.
00012     enum Mode {
00013         Standby = 0x0,
00014         Query = 0x1,
00015         Continuous = 0x2,
00016         None = 0x3
00017     };
00018     
00019     // Enum to make the returned output type more readable.
00020     enum Output {
00021         Heading = 0x0,
00022         RawX = 0x1,
00023         RawY = 0x2,
00024         X = 0x3,        
00025         Y = 0x4,
00026         Unknown = 0x5
00027     };
00028 
00029     HMC6352(PinName sda, PinName scl);
00030     ~HMC6352();
00031 
00032     // Address.
00033     inline int address() { return _address; }
00034     inline void setAddress(int address) { _address = address; }
00035     
00036     // Version.
00037     char getVersion();
00038     void setVersion(const char version);
00039     
00040     // Time delay.
00041     char getTimeDelay();
00042     void setTimeDelay(const char delay);
00043 
00044     // Summing.
00045     char getSumming();
00046     void setSumming(const char samples);
00047     
00048     // Heading.
00049     float getHeading();
00050     
00051     // Control
00052     void reset();
00053     
00054     void wakeUp();
00055     void goToSleep();
00056     
00057     void startCalibrate();
00058     void endCalibrate();
00059     void calibrate(int delay = 20);
00060     
00061     // Get the mode section of tyhe operation byte from RAM.
00062     HMC6352::Mode getMode();
00063     void setMode(HMC6352::Mode mode);
00064     
00065     // Save the operation byte in ram to eeprom.
00066     void saveOperation();  
00067     
00068     // Get the current output mode from the RAM register.
00069     HMC6352::Output getOutput();
00070     void setOutput(HMC6352::Output output);
00071 
00072     inline float version() const { return 0.1; }
00073 
00074 private:
00075     // Clears the contents of the buffer to 0x0
00076     void _clearBuffer();
00077     
00078     // Converts the values in the lower two bytes of the buffer to a heading.
00079     float _bufferToHeading();
00080     
00081     // Read or write to memory.
00082     void _readFromMemory(const char address, const bool eeprom);
00083     void _writeToMemory(const char address, const char data, const bool eeprom);
00084 
00085     // Set up a buffer to read and write data. The maximum amount of data 
00086     // returned or sent is 3 bytes.
00087     char _buffer[3];
00088 
00089     // Set up the i2c communication channel object.
00090     I2C _i2c;
00091        
00092     // To hold the address currently being used.
00093     int _address;
00094 
00095 };
00096 
00097 #endif