loading data in 74hc595

As per the circuit they are using Row scanning. The Column datas are loaded first through the shift registers and the Row is selected.
Then the second Row is selected and the column datas are loaded.

The Column data's are loaded with help of the following lines
COL_CLK
COL_DAT
COL_LOAD
COL_RESET
First give a pulse to the COL_RESET, so all the shift register outputs will be zero.
The load the data for the last bit in the data line and give a clock pulse.
Repeat the above so after 12th clock all the 12bit datas are moved inside the resisters.
Now give a clock pulse to COL_LOAD, so the data's on the resisters are loaded to the output pins.

hi,
Sir in my moving message display now I am facing problem of how to create an illusion.I am using 89c2051rd2bn.

Is it AT89C2051 or some other.

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HI,

Its 'P89c51RD2BN'.

ok, do you want to move the display or to display something fixedly.
What do you correctly mean the word illusion

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hi,
Yes sir I want to move the data.Illusion means,I want to know the
scrolling technique,in the same way as normal moving message board works.Please tell me the technique.

please check this topic, http://www.8051projects.info/forum/topic.asp?TOPIC_ID=140
i have given all the details clearly.

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hi,
I have already gone thru it,but nothing has clearly mentioned about 'persistance of vision' thing.Right now wt i have done is I am loading 5 byte data one by one and shifting it on successive columns.Like If i want to display lettor "E",then hex code for it is 0xff,0xff,0xdb,0xdb,0xc3.First i display 'ff' on the first column,clear it,then on the next column 'ff' again,clear it,then '0xdb' two times and then '0xc3' in the end.But all this is very slow and it doesnt look like letter 'E'.What exatly i have to do to look it like lettor 'E'.Plz help.Sorry to bother you again.

Ok, is the speed is fast or slow. If it is very fast then you cant see the correct image.
First make to display slow.
Can you post the code here, so that i can check it.

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#include<p89v51rd2.h>

/*P1 = R1 to R8(8 BITS OF DISPLAY BOARD)
* col_clk = P2.0
* col_dat = P2.1
* col_ldd = P2.2
* col_rst = p2.3
* col_clk = SH_CP(SHIFT REGISTER)
* col_dat = DS(SERIAL INPUT)
* col_ldd = ST_CP(STORAGE REGISTER)
* COL_RST = MR(master reset active low)
* OE = OUTPUT ENABLE (active low)*/


__sbit __at (0x90) row_1;
__sbit __at (0x91) row_2;
__sbit __at (0x92) row_3;
__sbit __at (0x93) row_4;
__sbit __at (0x94) row_5;
__sbit __at (0x95) row_6;
__sbit __at (0x96) row_7;
__sbit __at (0x97) row_8;

__sfr __at (0x90) p1;
__sbit __at (0xA0) sh_cp;
__sbit __at (0xA1) ds;
__sbit __at (0xA2) st_cp;
__sbit __at (0xA3) mr;
__sfr __at (0x89) TMOD;
__sfr __at (0x8D) TH1;
__sfr __at (0x8B) TL1;

//#define TR1 TCON_6
//#define TF1 TCON_7

void delay();
void clock2();
void clock();

unsigned int i;
unsigned int j;

void clock()
{

sh_cp = 0;
delay();
sh_cp = 1;
}


void clock2()
{
st_cp = 0;
delay();
st_cp = 1;
}


void delay()
{

for(i=0;i<=300;i++);
TR1=1; //start timer 1
while(!TF1); //check TF1 flag
TR1=0; //clear timer 1
TF1=0; //clear TF1 flag
}


void delay1()
{
for(i=0;i<=30000;i++);
}



void main()
{
char a = 0,b = 0,cnt = 0;

unsigned char font[5] = {0xff,0xff,0xdb,0xdb,0xc3};
TMOD=0x20; // * timer1 mode 2
TL1=0x00;
TH1=0x0EE; //5 ms delay

mr = 1; //RESET IS '0'
do
{
for(cnt = 0;cnt<=4;cnt++)
{
p1 = font[cnt];
clock(); //CLOCK FOR SHIFT REGISTER
clock2(); //CLOCK FOR STORAGE REGISTER
ds = 0; //SERIAL IN FOR 74HC595
delay1(); //DELAY FOR DATA TO REMAIN ON ONE COLUMN
a++;
if(a==5)
{
break;
}
}
}while(1);


}

First of all I am trying to display only one character.As i have used three shift registers I have restricted the output to only 5 columns,After that data repeats itself for 23 columns.And please tell me how to start the display again from the first column after 5th column.Ihis code is insufficient thats why I need ur help.

Thanx