Hel,at24c02 Problem

if anyone know it ,please tell me,thanks

i use at24c02 EEPROM in my circuit, just use one ,according to some data online, if you use 1 EEPROM

,then A0,A1,A2 can hang in the air,and i do it, but the circuit doesnt work,will it must connect to the ground?or a pull up resistance will success?

High Current Regulated Supply

The high current regulator uses an additional winding or a separate transformer to supply power for the LM317 regulator so that the pass transistors can operate closer to saturation and improve efficiency. For good efficiency the voltage at the collectors of the two parallel 2N3055 pass transistors should be close to the output voltage. The LM317 requires a couple extra volts on the input side, plus the emitter/base drop of the 3055s, plus whatever is lost across the (0.1 ohm) equalizing resistors (1volt at 10 amps), so a separate transformer and rectifier/filter circuit is used that is a few volts higher than the output voltage. The LM317 will provide over 1 amp of current to drive the bases of the pass transistors and assumming a gain of 10 the combination should deliver 15 amps or more. The LM317 always operates with a voltage difference of 1.2 between the output terminal and adjustment terminal and requires a minimum load of 10mA, so a 75 ohm resistor was chosen which will draw (1.2/75 = 16mA). This same current flows through the emitter resistor of the 2N3904 which produces about a 1 volt drop across the 62 ohm resistor and 1.7 volts at the base. The output voltage is set with the voltage divider (1K/560) so that 1.7 volts is applied to the 3904 base when the output is 5 volts. For 13 volt operation, the 1K resistor could be adjusted to around 3.6K. The regulator has no output short circuit protection so the output probably should be fused.

contact with me if you need the schametic

Rs-485 And Rs-232

i found this circuit in a site ,just carrying out it ,i use RS232 before ,will rs485 the same to it ,is there a differ in program

TL750L05,SN75LBC184

Lcd12864

/************************************************************
MCU:ATega16L 8MHz
************************************************************/

#include <mega16.h>
//#include <delay.h>
//#include <stdio.h>
#include "hzk.h"

/*LCD引脚定义 PB0-7对应LCD DB0-DB7*/
#define CS1 PORTA.6
#define CS2 PORTA.5
#define RS PORTA.2
#define RW PORTA.3
#define E PORTA.4
#define RST PORTA.7
#define SPEAK PORTA.0
#define LCDEL PORTA.1

#define MOTO1A PORTD.6
#define MOTO1B PORTD.7
#define MOTO2A PORTC.0
#define MOTO2B PORTC.1

#define HD7279CS 0
#define HD7279CLK 1
#define HD7279DATA 4
#define HD7279KEY 5

#define PD2 2
#define PD3 3

#define URSEL 7
//#define UMSEL 6
//#define UPM1 5
//#define UPM0 4
//#define USBS 3
#define UCSZ1 2
#define UCSZ0 1
//#define UCPOL 0

#define RXCIE 7
#define TXCIE 6
#define UDRIE 5
#define RXEN 4
#define TXEN 3
#define UCSZ2 2
#define RXB8 1
#define TXB8 0

#define RXC 7
#define TXC 6
#define UDRE 5
#define FE 4
#define DOR 3
#define OVR 3 /*This definition differs from the databook*/
#define PE 2
#define U2X 1
#define MPCM 0


typedef const struct
{
unsigned char X;
unsigned char Y;
}LCDPos;

LCDPos const LCDInfo[]={{0x28,0x00},{0x30,0x00},{0x38,0x00},{0x40,0x00},{0x48,0x00},
{0x50,0x00},{0x58,0x00},
{0x30,0x02},{0x38,0x02},{0x40,0x02},
{0x48,0x02},{0x50,0x02},
{0x30,0x04},{0x40,0x04},
{0x30,0x06},{0x40,0x06},{0x48,0x06}};
unsigned char LCDInfoBuf[17];

int Count = 1234;

void delay_us(int time)
{
do
{
time--;
}
while (time>1);
}

void Delay(int x)
{
int i,j;
for(j=0;j<x;j++)
{
for(i=0;i<250;i++);
}
}


unsigned char receive_byte(void)
{
unsigned char i,temp=0;
DDRD &= ~(1<<HD7279DATA);
delay_us(90);
for(i=0;i<8;i++)
{
temp=temp<<1;
PORTD |= (1<<HD7279CLK);
delay_us(10);
if((PIND & (1<<HD7279DATA))!=0)
temp|=0x01;
PORTD &= ~(1<<HD7279CLK);
delay_us(10);
}
DDRD |= (1<<HD7279DATA);
return temp;
}

void send_byte(unsigned char para)
{
unsigned char i;
PORTD &= ~(1<<HD7279CS);
delay_us(90);
for(i=0;i<8;i++)
{
if((para&0x80)==0x80)
PORTD |= (1<<HD7279DATA);
else
PORTD &= ~(1<<HD7279DATA);
PORTD |= (1<<HD7279CLK);
delay_us(10);
PORTD &= ~(1<<HD7279CLK);
delay_us(10);
para=para<<1;
}
}

void write7279(unsigned char cmd1, unsigned char cmd2)
{
send_byte (cmd1);
send_byte (cmd2);
PORTD |= (1<<HD7279CS);
}

void Rst7279(void)
{
send_byte(0xa4);
PORTD |= (1<<HD7279CS);
}

unsigned char Read7279(void)
{
unsigned char keyval;
if((PIND & (1<<HD7279KEY))==0)
{
send_byte(0x15);
keyval=receive_byte();
PORTD |= (1<<HD7279CS);
return keyval;
}
return 0xff;
}
void LCD_NOP(void)
{
unsigned char i;
for(i=0;i<50;i++);
// #asm("NOP");
}



void LCD_Write_ComL(unsigned char x)
{
CS1=0;
CS2=1;
LCD_NOP();
RS=0;
E=1;
LCD_NOP();
RW=0;
PORTB=x;
E=1;
E=0;
CS1=1;
CS2=1;
}

void LCD_Write_DatL(unsigned char x)
{
CS1=0;
CS2=1;
LCD_NOP();
RS=0;
E=1;
LCD_NOP();
RS=1;
RW=0;
PORTB=x;
E=1;
E=0;
CS1=1;
CS2=1;
}


void LCD_Write_ComR(unsigned char x)
{
CS1=1;
CS2=0;
LCD_NOP();
RS=0;
E=1;
LCD_NOP();
RW=0;
PORTB=x;
E=1;
E=0;
CS1=1;
CS2=1;

}

void LCD_Write_DatR(unsigned char x)
{
CS1=1;
CS2=0;
LCD_NOP();
RS=0;
E=1;
LCD_NOP();
RS=1;
RW=0;
PORTB=x;
E=1;
E=0;
CS1=1;
CS2=1;

}


void LCD_Init(void)
{
RST = 1;
RST = 0;
Delay(200);
RST = 1;
LCD_Write_ComL(0x3e);
LCD_Write_ComR(0x3e);
LCD_Write_ComL(0x3f);
LCD_Write_ComR(0x3f);
LCD_Write_ComL(0xc0);
LCD_Write_ComR(0xc0);
}


void LCD_Clr(void)
{
unsigned char i,j;

for(j=0;j<8;j++)
{
LCD_Write_ComL(0xb8|j);
LCD_Write_ComL(0x40);
LCD_Write_ComR(0xb8|j);
LCD_Write_ComR(0x40);
for(i=0;i<64;i++)
{
LCD_Write_DatL(0x00);
LCD_Write_DatR(0x00);
}
}
}


void CCW_PR(unsigned int neima,unsigned char X,unsigned char Y,unsigned char fan)
{
unsigned char k,com,dat1,hz;
unsigned int i;
Y=Y|0xb8;
LCD_Write_ComL(Y);
LCD_Write_ComR(Y);
if(neima<CB1B1)
hz=8;
else
hz=0;
if(X<0x40)
{
com=X+0x40;
LCD_Write_ComL(com);
k='L';
}
else
{
com=X;
LCD_Write_ComR(X); //Com=X-0x40+0x40
}
com=com&0x3f;
for(i=neima;i<(16+neima-hz);i++)
{
dat1=hzdot[i];
if(fan)
dat1=~dat1;
if(k=='L')
{
LCD_Write_DatL(dat1);
}
else
{
LCD_Write_DatR(dat1);
}
com++;
if(com==0x40)
{
LCD_Write_ComR(com);
k='R';
}
}
Y++;
LCD_Write_ComL(Y);
LCD_Write_ComR(Y);
if(X<0x40)
{
com=X|0x40;
LCD_Write_ComL(com);
k='L';
}
else
{
com=X;
LCD_Write_ComR(X); //Com=X-0x40+0x40
}
com=com&0x3f;
for(i=(16+neima-hz);i<(32+neima-hz-hz);i++)
{
dat1=hzdot[i];
if(fan)
dat1=~dat1;
if(k=='L')
{
LCD_Write_DatL(dat1);
}
else
{
LCD_Write_DatR(dat1);
}
com++;
if(com==0x40)
{
LCD_Write_ComR(com);
k='R';
}
}
}

void logo(void)
{

CCW_PR(CB5E7,0x4-2,0x06,0);
CCW_PR(CBBB0,0x14-2,0x06,0);

CCW_PR(CHAR_30,0x28-2,0x06,0);
CCW_PR(CHAR_31,0x30-2,0x06,0);
CCW_PR(CHAR_32,0x38-2,0x06,0);
CCW_PR(CHAR_33,0x40-2,0x06,0);
CCW_PR(CHAR_34,0x48-2,0x06,0);
CCW_PR(CHAR_35,0x50-2,0x06,0);
CCW_PR(CHAR_36,0x58-2,0x06,0);
CCW_PR(CHAR_37,0x60-2,0x06,0);
CCW_PR(CHAR_38,0x68-2,0x06,0);
CCW_PR(CHAR_39,0x70-2,0x06,0);
// CCW_PR(ASC0,0x78-2,0x06,0);
}

// External Interrupt 0 service routine
interrupt [EXT_INT0] void ext_int0_isr(void)
{
// Place your code here
if(PIND & (1<<PD3))
Count++;
else
Count--;
}

//主程序
void main(void)
{
unsigned int i;
unsigned char Key;
DDRB=0xff;
PORTB=0x00;
DDRA=0xff;

DDRC = 0xff;
PORTC = 0x00;

// Port D initialization
// Func7=Out Func6=Out Func5=In Func4=Out Func3=In Func2=In Func1=Out Func0=Out
// State7=0 State6=0 State5=P State4=0 State3=P State2=P State1=0 State0=0
PORTD=0x2C;
DDRD=0xD3;

// External Interrupt(s) initialization
// INT0: On
// INT0 Mode: Rising Edge
// INT1: Off
// INT2: Off
GICR|=0x40;
MCUCR=0x03;
MCUCSR=0x00;
GIFR=0x40;

Rst7279();
#asm("wdr");

#asm("SEI"); //开总中断

LCD_Init(); //LCD初始化
LCD_Clr(); //LCD清屏
MOTO1A = 0;
MOTO1B = 1;
MOTO2A = 0;
MOTO2B = 1;
SPEAK = 1;
LCDEL = 1;
logo();
Delay(200);
Delay(200);
while(1)
{
Key = Read7279();
if(Key != 0xff)
Count = Key;
LCDInfoBuf[0]=(Count/10000)%10;
LCDInfoBuf[1]=(Count/1000)%10;
LCDInfoBuf[2]=(Count/100)%10;
LCDInfoBuf[3]=(Count/10)%10;
LCDInfoBuf[4]=(Count)%10;
for (i=0;i<7;i++)
{
CCW_PR(LCDInfoBuf[i]*16,LCDInfo[i].X,LCDInfo[i].Y,0);
}

}
}

Pic16f877 I2c Programming

;****************************************************
;* 877I2CA.asm *
;* Very simple I2C sample program without Display *
;****************************************************
;*******************************************************************************
***********
; This source code provides a demonstration of the MSSP peripheral
; on the PIC16F877 MCU.
; The additional external subroutine are used for LCD Module
; PIC16F877 执行频率 : 4 Mhz
;
; The subroutines for I2C
; :I2C_BYTE_READ ; Read a Byte from Address I2C_Addr and put into I2C_Data
; :I2C_BYTE_WRITE ; Write to I2C_Addr with data @ I2C_Data
; :I2C_ACK_CHECK ; Wait until I2C device can accept further command
; :InitI2C ; Initial I2C Module
; :StartI2C ; Set START Condition !!
; :StopI2C ; Set STOP Condition
; :RstartI2C ; Set Restart Condition
; :RecI2C ; Enable I2C Receive
; :ACKI2C ; Initial ACK response
; :NACKI2C ; Initial NACK response
; :WaitI2C ; Wait until SSPIF Set
;*******************************************************************************
**************

list p=16f877
#include <p16f877.inc>

CBLOCK 0x20

I2C_Data
I2C_Addr

ENDC

w_temp EQU 0x72
status_temp EQU 0x73
pclath_temp EQU 0x74


;********************************************
; Locates startup code @ the reset vector
;********************************************
Reset_Addr
org 0x00
nop
goto Prog_Main
nop
nop

;***************************************************************************
;**** The Start Address of ISR is 0x004
;**** "PUSH" & "POP" 的使用范例 : 适用于像 PIC16F877 有SHARE BANK 的 PIC
;***************************************************************************

PUSH
movwf w_temp ; save off current W register contents
movf STATUS,w ; move status register into W register
movwf status_temp ; save off contents of STATUS register
movf PCLATH,W
movwf pclath_temp


POP
movf pclath_temp,W
movwf PCLATH
movf status_temp,w ; retrieve copy of STATUS register
movwf STATUS ; restore pre-isr STATUS register contents
swapf w_temp,f
swapf w_temp,w ; restore pre-isr W register contents
retfie ; return from interrupt


;----------------------------------------------------------------------

Prog_Main

BANKSEL TRISB ; Select Bank 1
movlw b'11000000' ; setup PORTB
movwf TRISB

BSF OPTION_REG,NOT_RBPU ; Disable PORTB pull-ups
BCF STATUS, RP0 ; Select Bank 0

call InitI2C

Main:

BANKSEL I2C_Addr
movlw 0x18
movwf I2C_Addr ;

BANKSEL I2C_Data ; Bank Switching, in case its bank is differ than I2C_Addr !!
movlw 0x99
movwf I2C_Data ;
call I2C_BYTE_WRITE ; Write to I2C Device when Address & Data are set OK

call I2C_ACK_CHECK ; Check the ACK response, Wait until the Device Acknowledge
; Issue !! The subroutine will not return until the device send ACK !!
;
;
BANKSEL I2C_Addr
movlw 0x18
movwf I2C_Addr ;
call I2C_BYTE_READ

nop ;
nop ;
goto $


;****************************************************************************
I2C_BYTE_READ: ; Read a Byte @ I2C_Addr to Buffer I2C_Data
;****************************************************************************

call StartI2C ; Set SSPCON2.SEN
call WaitI2C ; Wait PIR1,SSPIF

BANKSEL SSPBUF
movlw B'10100000' ; Write Command
movwf SSPBUF
call WaitI2C

BANKSEL I2C_Addr ; The "BANKSEL" may not necessary if I2C_Addr is @ the same bank with SSPBUF
movf I2C_Addr,W ; The Address you wish to "READ" from

BANKSEL SSPBUF
movwf SSPBUF
call WaitI2C

call RstartI2C ; Restart Condition !!
call WaitI2C ; Wait Until Restart OK !!

BANKSEL SSPBUF
movlw B'10100001' ; Write Read Command
movwf SSPBUF
call WaitI2C

call RecI2C ; Enable I2C Receive
call WaitI2C ; Wait Until Buffer Received
BANKSEL SSPBUF
movf SSPBUF,W ; Save to I2C_Data First !!
BANKSEL I2C_Data
movwf I2C_Data

call NACKI2C ; Initial NACK Response !!
call WaitI2C ; Wait until NACK sent out
call StopI2C ; Initial STOP Condition
call WaitI2C ; Wait Until STOP Condition Terminated
return

;****************************************************************************
I2C_ACK_CHECK: ; Read a Byte @ I2C_Addr to Buffer I2C_Data
;****************************************************************************

call StartI2C ; Set SSPCON2.SEN
call WaitI2C ; Wait PIR1,SSPIF

BANKSEL SSPBUF
movlw B'10100001' ; Read Command
movwf SSPBUF
call WaitI2C

BANKSEL SSPCON2
btfss SSPCON2,ACKSTAT ; Check ACKSTAT bit , 0 = ACK , 1 = NACK
goto ACK_Return
call StopI2C
call WaitI2C
goto I2C_ACK_CHECK

ACK_Return:
call StopI2C ; Initial STOP Condition
call WaitI2C ; Wait Until STOP Condition Terminated
return

;****************************************************************************
I2C_BYTE_WRITE: ; Write a Byte to I2C_Addr with I2C_Data
;****************************************************************************

call StartI2C ; Set SSPCON2.SEN
call WaitI2C ; Wait PIR1,SSPIF

BANKSEL SSPBUF
movlw B'10100000' ; Write Command
movwf SSPBUF
call WaitI2C

BANKSEL I2C_Addr ; The "BANKSEL" may not necessary if I2C_Addr is @ the same bank with SSPBUF
movf I2C_Addr,W ; The Address you wish to "READ" from
BANKSEL SSPBUF
movwf SSPBUF
call WaitI2C

BANKSEL I2C_Data
movf I2C_Data,W
BANKSEL SSPBUF
movwf SSPBUF
call WaitI2C

call StopI2C ; Initial STOP Condition
call WaitI2C ; Wait Until STOP Condition Terminated
return


;**********************************************************************
; The following subroutines perform commonly used I2C functions.
;**********************************************************************

InitI2C: ; The subroutine of I2C Initialization
BANKSEL TRISC
movlw B'00011000' ; Initial PortC,bit 3 & 4 as Input
movwf TRISC ; RC3 = SCL , RC4 = SDA

BANKSEL PORTC
movlw 0xff
movwf PORTC

movlw 0x09 ; This gives 100KHz I2C clock @ 4MHz
banksel SSPADD
movwf SSPADD
movlw b'10000000' ; Disable slew rate control.
banksel SSPSTAT
movwf SSPSTAT
movlw b'00000000' ;
movwf SSPCON2 ; Setup MSSP for continuous reception.
movlw b'00101000' ; Enable MSSP and setup for I2C master
banksel SSPCON ; mode.
movwf SSPCON
return


StartI2C ; Initiate the I2C START condition.
banksel SSPCON2
bsf SSPCON2,SEN
return

StopI2C ; Initiate the I2C STOP condition.
banksel SSPCON2
bsf SSPCON2,PEN
return

RstartI2C ; Initiate the I2C restart condition.
banksel SSPCON2
bsf SSPCON2,RSEN
return

NACKI2C
banksel SSPCON2
bsf SSPCON2,ACKDT ; Set the ACK bit
bsf SSPCON2,ACKEN ; Initiate the NACK sequence.
return

ACKI2C
banksel SSPCON2
bcf SSPCON2,ACKDT ; Clear the ACK bit
bsf SSPCON2,ACKEN ; Initiate the NACK sequence.
return

RecI2C
banksel SSPCON2 ;
bsf SSPCON2,RCEN ; Set the receive enable bit.
return


WaitI2C ; Poll for SSPIF
banksel PIR1
FLoop btfss PIR1,SSPIF
goto FLoop
bcf PIR1,SSPIF
return


;----------------------------------------------------------------------

end ; *********** End Of Program !!!!!