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/* 
Library for Sparkfun Si4703 breakout board.
Simon Monk. 2011-09-09

This is a library wrapper and a few extras to the excellent code produced
by Nathan Seidle from Sparkfun (Beerware).

Nathan's comments......

Look for serial output at 57600bps.

The Si4703 ACKs the first byte, and NACKs the 2nd byte of a read.

1/18 - after much hacking, I suggest NEVER write to a register without first reading the contents of a chip.
ie, don't updateRegisters without first readRegisters.

If anyone manages to get this datasheet downloaded
http://wenku.baidu.com/view/d6f0e6ee5ef7ba0d4a733b61.html
Please let us know. It seem to be the latest version of the programming guide. It had a change on page 12 (write 0x8100 to 0x07)
that allowed me to get the chip working..

Also, if you happen to find "AN243: Using RDS/RBDS with the Si4701/03", please share. I love it when companies refer to
documents that don't exist.

1/20 - Picking up FM stations from a plane flying over Portugal! Sweet! 93.9MHz sounds a little soft for my tastes,s but
it's in Porteguese.

ToDo:
Display current status (from 0x0A) - done 1/20/11
Add RDS decoding - works, sort of
Volume Up/Down - done 1/20/11
Mute toggle - done 1/20/11
Tune Up/Down - done 1/20/11
Read current channel (0xB0) - done 1/20/11
Setup for Europe - done 1/20/11
Seek up/down - done 1/25/11

The Si4703 breakout does work with line out into a stereo or other amplifier. Be sure to test with different length 3.5mm
cables. Too short of a cable may degrade reception.
*/

#ifndef SparkFun_Si4703_h
#define SparkFun_Si4703_h

#include "mbed.h"


class Si4703_Breakout
{
  public:
    Si4703_Breakout(PinName sdioPin, PinName sclkPin, PinName resetPin, Serial *pc);
    void powerOn();					// call in setup
    void powerOff();					// call in de-setup
	void setChannel(int channel);  	// 3 digit channel number
	int getChannel();				// returns the current channel
	int seekUp(); 					// returns the tuned channel or 0
	int seekDown(); 				
	void setVolume(int volume); 	// 0 to 15
    uint8_t getVolume(); 	// Returns The Current Volume (0 .. 15)

/*	void readRDS(char* message, long timeout);	 */
									// message should be at least 9 chars
									// result will be null terminated
									// timeout in milliseconds
	uint16_t getRegister(uint8_t regNum); // Returns The Value of a Single Register (0x00 .. 0x0F)
	void printRegs(); // Prints All of The Registers To The Serial Console

  private:
    PinName _resetPin;
	PinName _sdioPin;
	PinName _sclkPin;

    mbed::I2C *i2c_;
    mbed::Serial *pc;
    DigitalOut *_reset_;
    DigitalOut *_sdio_;

	void si4703_init();
	uint8_t readRegisters();
	uint8_t updateRegisters();
	int seek(bool seekDirection);

	uint16_t si4703_registers[16]; //There are 16 registers, each 16 bits large
	static const uint16_t  FAIL = 0;
	static const uint16_t  SUCCESS = 1;

	static const int  SI4703 = 0x20; //0b._001.0000 = I2C address of Si4703 - note that the Wire function assumes non-left-shifted I2C address, not 0b.0010.000W
	static const uint16_t  I2C_FAIL_MAX = 10; //This is the number of attempts we will try to contact the device before erroring out
	static const uint16_t  SEEK_DOWN = 0; //Direction used for seeking. Default is down
	static const uint16_t  SEEK_UP = 1;

	//Define the register names
	static const uint16_t  DEVICEID = 0x00;
	static const uint16_t  CHIPID = 0x01;
	static const uint16_t  POWERCFG = 0x02;
	static const uint16_t  CHANNEL = 0x03;
	static const uint16_t  SYSCONFIG1 = 0x04;
	static const uint16_t  SYSCONFIG2 = 0x05;
	static const uint16_t  SYSCONFIG3 = 0x06;
	static const uint16_t  TEST1 = 0x07;
	static const uint16_t  STATUSRSSI = 0x0A;
	static const uint16_t  READCHAN = 0x0B;
	static const uint16_t  RDSA = 0x0C;
	static const uint16_t  RDSB = 0x0D;
	static const uint16_t  RDSC = 0x0E;
	static const uint16_t  RDSD = 0x0F;

	//Register 0x00 - DeviceID
//   part# = 15:12, mfgid = 11:0

	//Register 0x02 - POWERCFG
	static const uint16_t  SMUTE = 15;
	static const uint16_t  DMUTE = 14;
	static const uint16_t  SKMODE = 10;
	static const uint16_t  SEEKUP = 9;
	static const uint16_t  SEEK = 8;
	static const uint16_t  DISABLE = 6;
	static const uint16_t  ENABLE = 0;

	//Register 0x03 - CHANNEL
	static const uint16_t  TUNE = 15;

	//Register 0x04 - SYSCONFIG1
	static const uint16_t  RDS = 12;
	static const uint16_t  DE = 11;

	//Register 0x05 - SYSCONFIG2
	static const uint16_t  SPACE1 = 5;
	static const uint16_t  SPACE0 = 4;
	static const uint16_t  SEEKTH = 8;

	//Register 0x06 - SYSCONFIG3
	static const uint16_t  SKSNR  = 4;
	static const uint16_t  SKCNT  = 0;

	//Register 0x0A - STATUSRSSI
	static const uint16_t  RDSR = 15;
	static const uint16_t  STC = 14;
	static const uint16_t  SFBL = 13;
	static const uint16_t  AFCRL = 12;
	static const uint16_t  RDSS = 11;
	static const uint16_t  BLERA = 9;
	static const uint16_t  STEREO = 8;
	static const uint16_t  RSSI = 0;
};

#endif