vidu4-4.c

dsp t&#7915 c&#417 b&#7843 n &#273 &#7871 n n&#226 ng cao 1

/*******************************************************************************
;	Vidu4-4.c la chuong trinh viet bang C30 de chay tren mot dsPIC			   *
;	Chuong trinh thuc hien viec sau: Khoi tao RTC DS1307, sau do doc thong tin *
;	tu RTC bang module I2C, gui thong tin thoi gian ve may tinh thong qua	   *
;	cong RS232 (dung cac chan I/O thay the)									   *
;*******************************************************************************

;	Tac gia				: Nguyen Quang Nam									   *

;	Don vi				: PIC Viet Nam										   *

;	Ten tap tin			: Vidu4-4.c											   *

;	Ngay				: 26/08/2006										   *

;	Phien ban			: 0.01												   *

;	Nhung tap tin can thiet khac: p30F4012.gld, p30f4012.h					   *

;	Cong cu duoc dung:	MPLAB 7.31											   *
;						C30 2.02 SE											   *
;						ASM30 2.14											   *
;						LNK30 2.14											   *
------------------------------------------------------------------------------*/
#include "p30f4012.h"

	_FOSC(CSW_FSCM_OFF & FRC_PLL4);		//Clock = 32 MHz
	_FWDT(WDT_OFF);
	_FBORPOR(MCLR_EN & PBOR_OFF & PWMxL_ACT_HI & PWMxH_ACT_HI);
	_FGS(CODE_PROT_OFF);

//------------------------------------------------------------------------------
//Cac hang so cua chuong trinh (gia tri tuc thoi dung trong chuong trinh)

#define	Fcy	8000000		//Tan so thuc thi lenh
#define	I2Cbaud	100000	//Toc do baud cua giao tiep I2C
#define	RSbaud	38400	//Toc do baud cua giao tiep RS232

//Cac prototype cho cac chuong trinh con
void Init_PORTS(void);
void Init_TMR1(void);
void Init_I2C(void);
void Wait_I2C(void);
void Write_I2C(unsigned char);
unsigned char Read_I2C(void);
void I2C_Fail(void);
void Init_UART1(void);
void Send_UART1(unsigned char);

//Cac bien toan cuc
unsigned short count, flag1, flag2, buf_idx, str_idx, i;
unsigned char buff[16] = {0xD0, 0x00, 0x00, 0x00, 0x67, 
						  0x01, 0x26, 0x08, 0x06, 0x90};
unsigned char str[16], temp;


//------------------------------------------------------------------------------
//Chuong trinh chinh
int main(void) {
	Init_PORTS();		//Khoi tao cac cong I/O
	Init_I2C();			//Khoi tao module I2C
	Init_UART1();		//Khoi tao module UART1
	Init_TMR1();		//Khoi tao Timer 1
	//Buoc 1, tao dieu kien START, cho hoat dong I2C hoan tat
	_SEN = 1;				//Tao ra dieu kien START
	Wait_I2C();				//Cho hoat dong I2C hoan tat
	//Buoc 2, ghi cac byte can thiet, cho va kiem tra ACK
	buf_idx = 0;			//Chinh con tro de bat dau tu dau bo dem
	flag1 = 0;				//Xoa co bao loi truoc khi ghi
	for (i = 10; i > 0; i--) {
		Write_I2C(buff[buf_idx++]);		//Ghi 1 byte vao RTC
		if (flag1 & 0x0001) I2C_Fail();	//Neu NACK thi xu ly loi
	};
	//Buoc 3, tao dieu kien STOP, cho hoat dong I2C hoan tat
	_PEN = 1;				//Tao ra dieu kien STOP
	Wait_I2C();				//Cho hoat dong I2C hoan tat

	while (1) {
		count = 11;
		while (count != 0);
		//Doc thong tin thoi gian tu RTC
		//Buoc 1, tao dieu kien START, cho hoat dong I2C hoan tat
		_SEN = 1;			//Tao ra dieu kien START
		Wait_I2C();			//Cho hoat dong I2C hoan tat
		//Buoc 2, ghi dia chi cua RTC, sap thao tac ghi vao RTC
		flag1 = 0;			//Xoa co bao loi truoc khi ghi
		Write_I2C(0xD0);
		if (flag1 & 0x0001) I2C_Fail();	//Neu NACK thi xu ly loi
		//Buoc 3, ghi dia chi cua thanh ghi sap thao tac
		Write_I2C(0x00);
		if (flag1 & 0x0001) I2C_Fail();	//Neu NACK thi xu ly loi
		//Buoc 4, tao dieu kien RESTART, cho hoat dong I2C hoan tat
		_RSEN = 1;			//Tao ra dieu kien RESTART
		Wait_I2C();			//Cho hoat dong I2C hoan tat
		//Buoc 5, ghi dia chi cua RTC, sap thao tac doc tu RTC
		Write_I2C(0xD1);	//Ghi dia chi cua RTC, chuan bi doc tu RTC
		if (flag1 & 0x0001) I2C_Fail();	//Neu NACK thi xu ly loi
		str_idx = 0;
		//Buoc 6, doc cac byte can thiet (tru byte cuoi cung), va ACK
		for (i = 2; i > 0; i--) {		//Vong lap doc 2 byte du lieu, va ACK
			flag2 &= 0xFFFE;
			temp = Read_I2C();
			str[str_idx++] = (temp & 0x0F) + '0';	//Chuyen so BCD thanh cac
			str[str_idx++] = (temp >> 4) + '0';		//ky tu bieu dien gia tri
			str[str_idx++] = ':';
		};
		//Buoc 7, doc byte cuoi cung va NACK
		flag2 |= 0x0001;
		temp = Read_I2C();
		str[str_idx++] = (temp & 0x0F) + '0';
		str[str_idx] = (temp >> 4) + '0';
		//Buoc 8, tao dieu kien STOP, cho hoat dong I2C hoan tat
		_PEN = 1;			//Tao ra dieu kien STOP
		Wait_I2C();			//Cho hoat dong I2C hoan tat
		//Vong lap xuat ky tu qua cong RS232
		for (i = 8; i > 0; i--) {
			Send_UART1(str[str_idx--]);
		};
		Send_UART1(0x0a);	//Xuat cap ky tu CR, LF
		Send_UART1(0x0d);
	};
}

//Chuong trinh con khoi tao cac cong I/O
void Init_PORTS(void) {
	LATE = 0xFFFF;			//Tat cac LED (anode chung) noi vao cong E
	TRISE = 0xFFFE;			//LED noi vao RE0
}

//Chuong trinh con khoi tao module I2C
void Init_I2C(void) {
	I2CCON = 0x8200;		//bit15=I2CEN, bit9=DISSLW (tat Slew Rate
							//Control cho cac toc do baud khac 400 kbps)
	I2CBRG = (((Fcy/I2Cbaud) - (Fcy/1111111))-1);
}

//Chuong trinh con cho hoat dong Master I2C sau cung hoan tat
void Wait_I2C(void) {
	while (!_MI2CIF);
	_MI2CIF = 0;
}

//Chuong trinh con xuat 1 byte qua module I2C
void Write_I2C(unsigned char d) {
	I2CTRN = d;
	Wait_I2C();
	if (_ACKSTAT) flag1 |= 0x0001;	//Bat co neu nhan duoc NACK
}

//Chuong trinh con doc byte tu I2C, che do Master
unsigned char Read_I2C(void) {
	unsigned char d;
	_RCEN = 1;				//Cho phep nhan byte
	Wait_I2C();				//Cho hoat dong I2C hoan tat
	d = I2CRCV;				//Lay byte da nhan dat vao d
	if (flag2 & 0x0001) _ACKDT = 1;		//Neu NACK thi bat ACKDT
	else _ACKDT = 0;		//Nguoc lai thi tat ACKDT
	_ACKEN = 1;				//Ghi bit ACK/NACK ra I2C bus
	Wait_I2C();				//Cho hoat dong I2C hoan tat
	return d;				//Tra byte da doc ve chuong trinh goi
}

//Chuong trinh con xu ly khi hoat dong I2C bi loi
void I2C_Fail(void) {
	_PEN = 1;				//Tao ra dieu kien STOP
	Wait_I2C();				//Cho hoat dong I2C hoan tat
	LATE &= 0xFFFE;			//Bat LED noi vao RE0 de bao loi
	while (1);				//Dung chuong trinh tai day
}

//Chuong trinh con khoi tao module UART1
void Init_UART1(void) {
	U1MODE = 0x8400;		//Alt I/O, 8-bit, no parity, 1 stop bit
	U1STA = 0x0400;			//bit10=UTXEN
	U1BRG = (((Fcy/RSbaud)/16)-1);	//38400 bps @ Fcy = 8 MHz
}

void Send_UART1(unsigned char d) {
	U1TXREG = d;				//Xuat 1 ky tu
	while (!U1STAbits.TRMT);	//Cho den khi truyen xong ky tu
}

//Chuong trinh con khoi tao Timer 1, tran sau moi 0,5 giay o muc xung 8 Mips
void Init_TMR1(void) {
	TMR1 = 0;			//Xoa so dem trong TMR1
	PR1 = 0x7A12;		//Nguong tran la 1 giay tuong ung voi clock = 32 MHz
	_T1IF = 0;			//Xoa co ngat cua Timer 1
	T1CON = 0x8030;		//Dung fcy lam clock, prescale = 1:256
	_T1IE = 1;			//Cho phep ngat khi Timer 1 tran
}

//Chuong trinh xu ly ngat Timer 1
void _ISR _T1Interrupt(void) {
	_T1IF = 0;			//Xoa co ngat
	count -= 1;			//Giam bien dem di 1 don vi
}