serial data transmission in 8051

hii,

I have been trying in vain to transmit and receive a string in 8051.
First character gets displayed on the lcd, but the rest do not.  I
shorted RXD and TXD pins.  The code in c is as follows:

void main()
{
unsigned char char_to_write[] = "hello, this is the data";
RECEIVED = 0;
init_timer();
init_lcd();
initialize_serial();
pass_cmd(0x80);
display_routine(char_to_write);
while(1);
}

void display_routine(unsigned char *this_is)
{
while(*this_is)
	{
	SBUF = *this_is++;
	TI = 1;
	while(!RECEIVED);
	RECEIVED = 0;
	}
}

void init_timer() \\for 4800 baud rate
{
TICK = 0;
EA = 1;
ET0 = 1;
TMOD = 1;
TH0 = 0XFC;
TL0 = 0X18;
}

void initialize_serial()
{
SCON = 0X50;
TMOD = 0X20;
TH1 = 0XF3;
TR1 = 1;
EA = 1;
ES = 1;
}


void serialint() interrupt 4
{
if(TI)
	TI = 0;
if(RI)
	{
	pass_data((unsigned char)SBUF); // displays SBUF value on lcd.
	RI = 0;
	RECEIVED = 1;
	}
}

I dont find any problem with lcd display function or timer function.
Any help will be appreciated. Thanx,
digitalBug

"DigitalBug" <sharaf_cool@yahoo.co.in> wrote in message 
news:1124721940.713597.313290@z14g2000cwz.googlegroups.com...
> hii,
>
> I have been trying in vain to transmit and receive a string in 8051.
> First character gets displayed on the lcd, but the rest do not.  I
> shorted RXD and TXD pins.  The code in c is as follows:
>
> void main()
> {
> unsigned char char_to_write[] = "hello, this is the data";
> RECEIVED = 0;
> init_timer();
> init_lcd();
> initialize_serial();
> pass_cmd(0x80);
> display_routine(char_to_write);
> while(1);
> }
>
> void display_routine(unsigned char *this_is)
> {
> while(*this_is)
> {
> SBUF = *this_is++;
> TI = 1;
> while(!RECEIVED);
> RECEIVED = 0;
> }
> }
>
> void init_timer() \\for 4800 baud rate
> {
> TICK = 0;
> EA = 1;
> ET0 = 1;
> TMOD = 1;
> TH0 = 0XFC;
> TL0 = 0X18;
> }
>
> void initialize_serial()
> {
> SCON = 0X50;
> TMOD = 0X20;
> TH1 = 0XF3;
> TR1 = 1;
> EA = 1;
> ES = 1;
> }
>
>
> void serialint() interrupt 4
> {
> if(TI)
> TI = 0;
> if(RI)
> {
> pass_data((unsigned char)SBUF); // displays SBUF value on lcd.
> RI = 0;
> RECEIVED = 1;
> }
> }
>
> I dont find any problem with lcd display function or timer function.
> Any help will be appreciated. Thanx,
> digitalBug

I think you lcd rutine is to slow, so the string on the serial port is 
transmitted before you have written 1 char in your lcd...

recieve the whole string before you write it to the lcd... or at least move 
it out from the IRQ rutine and have a recieve buffer... then you can start 
to write out before...

Kasper 

Repzak wrote:

> recieve the whole string before you write it to the lcd... or at
> least move it out from the IRQ rutine and have a recieve buffer...
> then you can start to write out before...

Yes, have your serial ISR move the data into a buffer, and nothing else. 
Then have your background (app/main/idle) loop polling the buffer for 
new data and write to the LCD from there.

Regards,
Mark

Hii folk,

It works... Thank you repzak and mark for your generous help.
Sharaf