sending a bit of a char ro any port pin

I am not a C51 guy, but why don't you try something like this:

P1_0 = (a & 0x1) ;

to place bit 0 on the pin.

I am not a C51 guy, but why don't you try something like this:

P1_0 = (a & 0x1) ;

to place bit 0 on the pin.

use a buffer like MyBuffer[20], as you know you can now put 19 characters in this buffer.
if your strings are fixed for example always 5 chars, test if the 6th char is pressed, or use
* or # or any other button for entering the string. Don't forget to collect the previous chars in the buffer.

for example:

  char MyBuffer[20],input;  // buffer and current key input
  int i=0;   // counter

  while (input != '#')  // "#" key is assumed as ENTER key
  {
    input = MyBuffer[i];
    i++;
  }

hope this helps

didn't he want to send data, rather than to receive it?

for the transmit the code needs o be this

use a buffer like MyBuffer[20], as you know you can now put 19 characters in this buffer.
if your strings are fixed for example always 5 chars, test if the 6th char was sent, or use
$ or any other characteur for finnishing the string. Don't forget to send the previous chars in the buffer.

for example:

  char MyBuffer[20],output;  // buffer and current display output
  int i=0;   // counter

  while (output != '$')  // "$" key is the end of dos string
  {
    MyBuffer[i] = output;
    i++;
  }

hope this helps better whot the last do

yavuz, yavuz, yavuz...
help your friedn with something else rather than chewed C code...how about showing him how to work/configure a peripheral like the UART? I cannot help him with that, as I don't know the processor (do you...?)

by the way, yavuz, your code can buffer overflow without any problem. try to deal with 21 characters...

what is the problem?

you make the enhanmecent like this; now here you go to 25 characters

 char MyBuffer[25],output;  // buffer and current display output

yes and i gave code in the other place for uart but it was used.

yavuz,
obviousely, you cannot infinitely increase the size of your buffer! that is a big problem indeed! I have corrected your code below to make is circular buffer. there are of course many other options!

char MyBuffer[20],output;  // buffer and current display output
  int i=0;   // counter

  while (output != '$')  // "$" key is the end of dos string
  {
    MyBuffer[i % 20] = output;
    i++;
  }

the modulus operator is just about the slowest thing you can use in '51 c code.

thus, make circular buffer size a power of two and then the access is
... [index & (BUFFER_SIZE - 1)]

Erik

yap, correct. but I was trying to save lives....

Modulus and circular buffers aside ...

The code is incomplete, non-functional, and rubbish anyway.

And it doesn't even answer the OPs original question!

well, that's why I wrote
I cannot help him with that, as I don't know the processor (do you...?)

This is a funny thread. The answer to the OPs question is available in the fifth post. After that follows incomplete code that tries to answer a question I haven't seen.

What this thread needs, is for the OP to read post #2 and come back with more info, i.e. may the original question be the result of a misunderstanding.