I need help, I have a circuit setup with input (74hc165) and output (74hc595) shift registers. Am trying out with 4x4 matrix keypad (for thats what i have available for now) but this will end up 8x8 matrix keypad. I have put a firmware together and that is running ok and returning the key press. But my challenge is; how can I make Arduino loop function wait for a keypress. Presently it continously returns the last key pressed. I played around it without luck; I adopted the code below from online, this only wait for the initial time(ie without any key pressed), the moment a key is press, it runs with it and return that key until another is press.
const unsigned int DebounceDelay = 15;
const long AutoRepeatDelay = 125;
const unsigned int KeyWait = 25;
int WaitKey()
{
int key;
// wait for all keys to be released
key = KeyDown();
if (key == 0)
{
long repeatTime = millis() + AutoRepeatDelay;
do
{
// wait a bit
delay(KeyWait);
// see if a key is still down
if (KeyDown() != 0)
{
// debounce the key release
delay(DebounceDelay);
if (KeyDown() != 0)
{
key = 0;
break;
}
else if (millis()>repeatTime)
{
// effect auto-repeat
break;
}
//}
}
} while (true);
/// }
// wait for a key to be pressed
while (key != 0)
{
key = KeyDown();
if (key == 0)
{
// debounce the key down
delay(DebounceDelay);
}
else
{
delay(KeyWait);
}
}
}
return key;
}
