simpleSA/si4432.h

/*
 *	"Si4432.h"
 *
 *	Added to the program in Version 1.1 by John Price (WA2FZW):
 *
 *	Modified in Version 1.7 to create a "true" class/object implementation for
 *	handling the Si4432 modules.
 *  Modified by M0WID for 2.6 to remove dependencies on tinySA specific include files
 *  and use SPI class pointer in the constructor
 *
 *	This file contains symbolic definitions for all the Si4432 registers that are
 *	used in the program and symbols for some of the values that get loaded into or
 *	read from them. For full explanations (whether you can make sense out of them
 *	or not) of the registers please refer to the  "Silicon Labs Si4430/31/32 - B1"
 *	data sheet and "Silicon Labs Technical Note A440".
 *
 *	Some of the functions in here apply only to the receiver and some apply only
 *	to the transmitter. The "Init" functions remember which type of module is
 *	being initiated. Eventually we will use that to avoid doing things which don't
 *	make sense for one type or the other.
 *
 *	It also contains some structure definitions and some data elements we keep
 *	to ourselves.
 */

#ifndef SI4432A_H_
#define SI4432A_H_							// Prevent double inclusion

#include <Arduino.h>						// Basic Arduino definitions
#include <SPI.h>							// SPI bus related stuff

#define ELEMENTS(x)    ( sizeof ( x ) / sizeof ( x[0] ))

/*
 *	In the original program, these were the indicies into the "SI_nSEL" array used
 *	to indicate whether the receiver or transmitter module was selected to perform
 *	an operation on. 
 *
 *	In this implementation, the "_type" variable is set to one or the other in the
 *	initialization functions to remember which type we are. 
 *
 *	The "_type" value will eventually be used to prevent certain operations from
 *	being accidently performed on the wrong type of module; for example, setting the
 *	RBW ("SetRBW") is not valid for the transmitter module or "Get_RSSI" is only
 *	applicable to the receiver module.
 */

	#define	RX_4432		0					// Receiver is Si4432 #0
	#define	TX_4432		1					// Transmitter is Si4432 #1
	#define TGIF_4432	2
	#define TGLO_4432	3


/*
 *	The maximum SPI bus speed for the Si4432 is 10MHz. It operates in SPI MODE0 and
 *	the address and data are transmitted MSBFIRST.
 *
 *	That being the case, the following definitions will be used in the read and write
 *	functions to set those parameters before each transaction:
 */

	#define	BUS_SPEED	10000000				// 10 MHz
	#define	BUS_MODE	SPI_MODE0				// Data is read on rising edge of the clock
	#define	BUS_ORDER	MSBFIRST				// Send stuff MSB first


/*
 *	"WRITE_DELAY" is a time in microseconds that seems to be required after each write
 *	to one of the Si4432 registers on some (but not all) Si4431 modules. You can try
 *	reducing the value to '1', but if you have problems getting one of them to actually
 *	work, try increasing the value. '25' is the value that works for my modules.
 */

	#define	WRITE_DELAY	25


/*
 *	Si4432 Registers used in the program and bit definitions for some of them:
 */

#define		REG_IS2		0x04				// Interrupt Status #1
	#define	ICHIPRDY	0x02				// Chip ready

#define		REG_INT1	0x06				// Interrupt enable register 1

#define		REG_OFC1	0x07				// Operating & Function Control 1
	#define	XTON		0x01				// Ready mode on (see datasheet)
	#define	PLLON		0x02				// PLL on
	#define	RXON		0x04				// Receiver on
	#define	TXON		0x08				// Transmitter on
	#define	X32KSEL		0x10				// Use external 32KHz crystal
	#define ENLBD		0x40				// Device enabled
	#define	SW_RESET	0x80				// System reset

#define		REG_COLC	0x09				// Crystal Oscillator Load Capacitance

#define		REG_MCOC	0x0A				// Microcontroller Output Clock

#define		REG_GPIO0	0x0B				// GPIO0 Configuration

#define		REG_GPIO1	0x0C				// GPIO1 Configuration

#define		REG_GPIO2	0x0D				// GPIO2 Configuration

#define		REG_IFBW	0x1C				// IF Filter Bandwidth

#define		REG_AFCGSO	0x1D				// AFC Loop Gearshift Override

#define		REG_AFCTC	0x1E				// AFC Timing Control

#define		REG_CRGO	0x1F				// Clock Recovery Gearshift Override

#define		REG_CROSR	0x20				// Clock Recovery Oversampling Ratio

#define		REG_CRO2	0x21				// Clock Recovery Offset 2

#define		REG_CRO1	0x22				// Clock Recovery Offset 1

#define		REG_CRO0	0x23				// Clock Recovery Offset 0

#define		REG_CRTLG1	0x24				// Clock Recovery Timing Loop Gain 1

#define		REG_CRTLG0	0x25				// Clock Recovery Timing Loop Gain 0

#define		REG_RSSI	0x26				// Received Signal Strength Indicator

#define		REG_AFCLIM	0x2A				// AFC Limiter

#define		REG_OOKC1	0x2C				// OOK Counter Value 1

#define		REG_OOKC2	0x2D				// OOK Counter Value 2

#define		REG_SPH		0x2E				// Slicer Peak Hold

#define		REG_DATAC	0x30				// Data access control

#define		REG_AGCOR1	0x69				// AGC Override 1
	#define	LNAGAIN		0x10				// LNA enabled
	#define	AGCEN		0x20				// AGC enabled
	#define	PGAGAIN		0x0F				// PGA Gain value in dB/3
	#define	AGC_ON		0x60				// Turn the AGC on

#define		REG_TXPWR	0x6D				// Transmitter Power

#define		REG_FOFF1	0x73				// Frequency Offset registers
#define		REG_FOFF2	0x74

#define		REG_FBS		0x75				// Frequency Band Select
	#define	SBSEL		0x40
	#define	HBSEL		0x20
	#define	F_BAND		0x1F

#define		REG_NCF1	0x76				// Nominal Carrier Frequency 1

#define		REG_NCF0	0x77				// Nominal Carrier Frequency 0


enum {DO_NOT_USE, USE_IN_AUTO, AVAILABLE};	// bandpass filter status values

typedef struct
{
	float   bandwidth10;		// Just one decimal point to save space (kHz * 10)
	unsigned long   settleTime;		// Narrower bandwidth filter needs longer settling time before RSSI is stable
	uint16_t   dwn3_bypass;		// Bypass decimate by 3 stage if set
	uint16_t   ndec_exp;			// IF Filter decimation rate = 2^ndec_exp.  larger number -> lower bandwidth (range 0-5)
	uint16_t   filset;			// IF Filter coefficient set.  Predefined FIR filter sets (1-15)
	uint16_t   Status;			// 0 = DO_NOT_USE, 1 = USE_IN_AUTO, 2 = AVAILABLE
} bandpassFilter_t;

class Si4432
{

public:

explicit	Si4432 ( SPIClass* spi, uint8_t cs, uint8_t id );		// Constructor

bool		Init ( uint8_t cap );						// Initialize the SI4432 module, return false if failed
//bool		TX_Init ( uint8_t cap, uint8_t power );		// Initialize the transmitter module, return false if failed

void		SetFrequency ( uint32_t Freq );  			// Set module's frequency
uint32_t	GetFrequency ();               				// Get the module's frequency 
uint32_t	ReadFrequency ();							// Read frequency from SI4432

void 		SetOffsetFreq ( int32_t freq );				// Set a frequency offset from the nominal frequency
void		SetOffset ( int32_t offset );				// Offset based on number of offset increments

void		SetPowerReference ( int freq );				// Set the GPIO output for the LO
void		SetDrive ( uint8_t level );					// Sets the drive level

float		SetRBW ( float reqBandwidth10, unsigned long* delaytime_p, uint16_t* filter_p );    // "reqBandwidth" in kHz * 10

void 		SetPreampGain ( int gain );					// Sets preamp gain
int			GetPreampGain ();							// Get current gain register
int			ReadPreampGain ();							// Read gain register from SI4432
bool 		PreAmpAGC();								// Reads the register and return true if agc set to auto
bool 		GetPreAmpAGC ();								// Return true if agc set to auto

uint8_t		GetRSSI ();									// Get Receiver Signal Strength

void		RxMode ();									// Put module in RX mode
void		TxMode ( uint8_t level );					// Put module in TX mode
void		ReadyMode ();								// Put module in READY mode, crystal on, PLL off
uint8_t		GetMode ();
void		SetMode (uint8_t newMode);

void		Tune ( uint8_t cap );						// Set the crystal tuning capacitance

void		WriteByte ( byte reg, byte setting );		// Write a byte of data to the specified register
uint8_t 	ReadByte  ( uint8_t reg );					// Read a byte of data from the specified register

uint16_t	GetBandpassFilter10 ( uint8_t index );		// Return the filter bandwidth for selected element of bandpassFilters array
uint8_t		GetBandpassFilterCount ();

void		PrintRegs ();								// Dump all the Si4432 registers


/*
 *	These are common functions that are only accessible from within the object.
 */

private:

void		SubInit ();								// Initialization common to both modules
bool		Reset ();								// Initialize the module


/*
 *	Private data elements:
 */

uint8_t		_cs;					// Chip select pin number for the module
float   	_bw;					// Current bandwidth setting
uint32_t	_dt;					// Current delay time setting
uint8_t		_pwr;					// Current power output (TX only?)
uint8_t		_type;					// Transmitter or receiver
uint8_t		_capacitance;			// Crystal load capacitance
SPIClass*   _spi;					// Pointer to the SPI object
int			_hbsel;					// High band (1) or low band (0)
uint8_t		_fbs;					// Current value of frequency band select register
uint8_t		_ncf1;					// Current value for most significant byte of carrier
uint32_t	_freq;					// Current actual frequency
									// can be different to that requested due
									// to resolution)
int			_gainReg;				// value of the gain reg written to the device									
bool		_autoGain;				// true if auto

static		bandpassFilter_t _bandpassFilters[];
static		uint8_t 		 _bpfCount;				// Number of elements in bandpassFilters array

};									// End of class "Si4432"

#endif