Digital Clock using 8051 and RTC DS12C887

[poovi]

HI,

 

       I tried to implement the circuit but  was unable to get any message on the LCD. Also I did not clearly understand how the initial setting of the circuit is done i.e connecting P3.3 = 0 and start =0 and setting hour and minute and then removing them. Please help me as I am trying to implement this from a long time and seem to be getting nowhere

 

 

Also is a picture of the microcontroller board that I am using. There is no availability of connection from pin 30 so I have soldered a wire to the board. But there is still no display on the LCD but the gree LED on the board flickers. What does it stand for?

 

 

 

 

 

 

 

[AJISH ALFRED]

the lcd is too brighter than normally it should be. thanks for posting the image. I think you’ve connected pin 15 and pin 16 directly to vcc and ground respectievely without using a current limiting resistor. Suggest you to post the circuit diagram again, in this post it is not legible

[poovi]

                                               I have checked the LCD separately using a sample code and it displays properly.  So I decided to check the RTC separately and gave the code as below. The code executed correctly on Kiel Simulator. (it constantly displayed 16:55:58) However when I burnt the same code into the microcontroller and connected the hardware, there was no output on Hyper terminal.. ( I am not exactly sure how to use Hyper terminal) .  PLease help me as I need to submit this as my project

 

       

 

//Program to interface RTC DS12C887 with 8051 microcontroller (AT89C51)
#include<reg51.h>
#include<absacc.h>
 char hr, min, sec;
 
void delay(int time)
{
    int i,j;
    for(i=0;i<time;i++)
    for(j=0;j<1275;j++);
}

serial(char x) // Function to transmit data serially using RS232
{
    
    SBUF=x;
    while(TI==0);
    TI=0;
}

void bcdconv(char mybyte) // Function to convert data into BCD format.
{
    char x,y;
    x=mybyte&0x0F;
    x=x|0x30;
    y=mybyte&0xF0;
    y=y>>4;
    y=y|0x30;
    serial(y);
    serial(x) ;
}

void main()
{
    TMOD=0x20;
    TH1=0xFD;
    SCON=0X50;                          
    TR1=1;
    delay(220);
    XBYTE[10]=0x20;
    delay(20);
    XBYTE[10]=0x30;
    XBYTE[11]=0x83;
    XBYTE[0]=0x55;
    XBYTE[2]=0x58;
    XBYTE[4]=0x16;
    XBYTE[7]=0x02;
    XBYTE[8]=0x02;
    XBYTE[9]=0x02;
    XBYTE[11]=0x03;
    while(1)
    {
        XBYTE[10]=0x20;
        delay(500);
        hr=XBYTE[4];
        bcdconv(hr);
        serial(‘:’);
        min=XBYTE[2];
        bcdconv(min);
        serial(‘:’);
        sec=XBYTE[0];
        bcdconv(sec);
        serial(0x0D);
        serial(0x0A);
    }
}

[AJISH ALFRED]

You need to set the following things exactly same on your code and the hyperterminal
baud rate = 9600
data bits = 8
start bit = 1
stop bit = 1
parity bit = 0
hardware flow = none (only in hyperterminal)

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