i2c.h

renasas m16c上实现iic通信的源代码.

// ./i2c.h start
//
/*----------------------------------------------------------------------------------**
** 	Driver:			I2C Bus Device Driver Package for M16C/62 serires MCUs.         **
** 	(c) 1999 		Mitsubishi Electronics America, Inc.                            **
** 					Three Diamond Lane                                              **
** 					Durham, North Carolina 27704  USA                               **
** 					Ph 919-479-3333                                                 **
** 	File:			i2c.h                                                           **
** 	Discription:	This multi-master driver provides the software interface to the **
** 					I2C Bus hardware of the M3062x series of Mitsubishi's MCU.      **
**----------------------------------------------------------------------------------*/

/*-----------------------------------------------**
** 		  	Please make the following settings.  **
**-----------------------------------------------*/

#define MAIN_CLOCK		16e6	// Main Clock speed of MCU.
#define CLOCK_DIV		1		// Main Clock divide ratio.
#define I2C_BUS_SPEED	200e3	// I2C Bits per second rate. 

#define GET_ERROR_MES_RET	0	// 0 for beggining of message "Use for debugging"
								// 1 for error value.

//------- Do not edit below this line. ------------------------------------------------
	 
// The following 7 functions should be called by the user's application.
// iic_ini is called to initialize slave operations.   
	extern void iic_ini(unsigned char,unsigned char*);
// init_i2c_busy_flag is called to initailization baudrate, main clock speed, ETC.
	extern void init_i2c_mas_func(void);
// iic_stop is called to disable I2C bus communications.  
	extern unsigned char iic_stop(void);
// iic_mr_start is called to begin master read data tranfers. 
	extern unsigned char iic_mr_start(unsigned char,unsigned char*,unsigned char);
// iic_mw_start is called to begin master write dta transfers. 
	extern unsigned char iic_mw_start(unsigned char,unsigned char*,unsigned char);
//	check_i2c_bus_statur is call to check the status of the bus opperation.
	extern unsigned char check_i2c_bus_status(unsigned char i);
//  To get the current error code for the status call Get_error_mass
	extern char far* Get_error_mass(void);

#pragma PARAMETER iic_ini(R0H,A0)
#pragma PARAMETER iic_mr_start(R0H,A0,R0L)
#pragma PARAMETER iic_mw_start(R0H,A0,R0L)
#ifndef I2C_C
extern unsigned char lng;			// Number of data bytes transfered by Master.
extern unsigned char I2C_bus_busy;	// Bus busy flag.  
extern unsigned char status;			// Current status of bus.
extern unsigned char iic_ram[128];	// Slave Ram.
#else
// The next two functions listed are for internal processing only.  
void iic_mw_end(unsigned char MW_STATUS, unsigned char MW_LNG);
void iic_mr_end(unsigned char MR_STATUS,unsigned char MR_LNG);	   

// --------------------------------------------------------------------------------------------------
// The following defines set up static values used in assembley langage code.  
// Original times "DELAY_2USEC" are based on 16MHZ main clock, clock divide ratio of 1, and 
// BAUD rate of 100k bits per second.  The delay values  and baudrate will automatically 
// be properly programmed when this library is compiled for the target system.  
#define I2C_BUS_BAUDRATE	((unsigned char) ((MAIN_CLOCK / (2 * CLOCK_DIV * I2C_BUS_SPEED)) - 1) )
#define COUNTER_RATIO 	((float)((CLOCK_DIV * 5.0)/MAIN_CLOCK)) // Delay_counter executes in 5 clock cycles.
#define BAUD_RATE_ADJUST ((float)(100e3 / I2C_BUS_SPEED )) 
#define DELAY_2USEC		((unsigned int)(2e-6 * BAUD_RATE_ADJUST / COUNTER_RATIO ))
#define DELAY_4USEC		((unsigned int)(4e-6 * BAUD_RATE_ADJUST / COUNTER_RATIO ))
#define DELAY_5USEC		((unsigned int)(5e-6 * BAUD_RATE_ADJUST / COUNTER_RATIO ))
#define DELAY_15USEC	((unsigned int)(15e-6 * BAUD_RATE_ADJUST / COUNTER_RATIO ))
#define DELAY_20USEC	((unsigned int)(20e-6 * BAUD_RATE_ADJUST / COUNTER_RATIO ))
// --------------------------------------------------------------------------------------------------
#endif


/*-----------------------------------------------------------**
** Use enum data type for both MW_END and MR_END functions.  **
**-----------------------------------------------------------*/

enum I2C_status_Responses {
Master_transmission_completed_normally = 0,
Slave_returned_NACK_in_the_first_byte,
Slave_returned_NACK_in_data_region,
BUS_competition_detected_and_master_operation_completed,
Improper_start_condition_detected,
Improper_stop_condition_detected
};

/*-------------------------------------------**
**  Use enum data tyype for status of bus.   **
**-------------------------------------------*/

enum I2C_status_flags {
Not_busy	= 0,
Busy,
Set_flag
};


// ./i2c.h end