btnp

btnp [[id, [hold], [period] ] -> pressed

Parameters

id : the id (0..31) of the button we wish to interrogate - see the key map for reference
hold : the time (in ticks) the button must be pressed before re-checking
period : the the amount of time (in ticks) after hold before this function will return true again.

Output:

pressed : button is pressed now but not in previous frame (true/false)

Description

This function allows you to read the status of one of TIC's buttons. It returns true only if the key has been pressed since the last frame.

You can also use the optional hold and period parameters which allow you to check if a button is being held down. After the time specified by hold has elapsed, btnp will return true each time period is passed if the key is still down. For example, to re-examine the state of button '0' after 2 seconds and continue to check its state every 1/10th of a second, you would use btnp(0, 120, 6). Since time is expressed in ticks and TIC runs at 60 frames per second, we use the value of 120 to wait 2 seconds and 6 ticks (ie 60/10) as the interval for re-checking.

Example

-- btnp demo: move the rectangle in 10 pixels step,
-- every time one direction keys is pressed.
-- Keep the key pressed for more than 1 second to have
-- the rectangle move every tenth of seconds.

x=120
y=80

cls(12)
function TIC()

    if btnp(0,60,6) then y=y-10 end
    if btnp(1,60,6) then y=y+10 end
    if btnp(2,60,6) then x=x-10 end
    if btnp(3,60,6) then x=x+10 end

    rect(x,y,10,10,8)
end