Waiting for a button release in C

[cloudsword]

So I'm writing this program to write into hyperterminal using button presses and here is a snippet of my code

  if (button1==0)//button is pressed
{
  		uart_transmit('L');
  }
  if (button2==0)
  	
  {
  		uart_transmit('U');
  }
  if (button3==0)
  {
  		uart_transmit('K');
  }
  if (button4==0)
  {
  		uart_transmit('E');
	}

I want it to wait until [button]=1 (ie the button is released) before doing it's next action
How would I do this?

[anduril462]

You have to track when button1 was pressed, and then once it's pressed (has a 0 value), wait for it to be released (go back to 1/non-zero).

[cloudsword]

and how would I do that code wise

[CommonTater]

Give a little thought to ....

if button1 == 0
 {send to uart 
 while(button1 == 0); }

[anduril462]

Maybe a second variable, button1_old. Then, everytime you check button states, you move the value in button1 to button1_old, and update button1 with the new value. If button1_old is 0 and button1 is 1, you know button 1 was released.

[bithub]

What operating system are you using (or is this an embedded device)?

[anduril462]

Give a little thought to ....

Yeah, after I hit the "post" button, I thought I should have just told the OP to actually try and think of a solution for more than 30 seconds. So...

@cloudsword: Actually spend time thinking about solutions before giving up and asking for the answer. "Great question asking skills" is a sure way to get your resume thrown out. "Great problem solving skills" is a much better trait to possess. The only way you'll get there is by trying to think things through on your own, and try them out. The world wont end if you try something and it doesn't work.

[CommonTater]

cloudsword: Actually spend time thinking about solutions before giving up and asking for the answer. "Great question asking skills" is a sure way to get your resume thrown out. "Great problem solving skills" is a much better trait to possess. The only way you'll get there is by trying to think things through on your own, and try them out. The world wont end if you try something and it doesn't work.

LOL... it's far more likely to end because we stupidly tried something that DID work....

[cloudsword]

Thanks CommonTater! I've been working with HDL's so long that I did not consider using a while loop.