Hi all, I connect the pin PA2 (pin42 of Cypress CY7C68013 56-pin SSOP) to a push button. When I push the button, there will be a 3.3 voltage applied to pin PA2. I can enable pin PA2 for input and read its state. However, I thinks it is not good solution because user normally presses and releases the push button in very short time. Therefore, when the firmware reads the state of IOA2, user already released the button -> the push button event will be not recorded. Is there any method to raise interrupt when PA2 pin is set? Delrina Chang,
User cannot press a key so shortly that normal micro cannot detect it - the human reaction times are in the order of 100mS. The shortest pulse you can expect would be at least 50mS and it heavily depends on the key type. So, if you sample the key 100 times a second, you would never miss a key press... - Dejan
User cannot press a key so shortly that normal micro cannot detect it That depends on the mechanical construction of the key, and the determination of the user ;-)
I would really want to see a human pressing ANY type of key shorter than 1mS. I have tested some endless rotary switches and even there the shortest pulses were about 5-10mS... - Dejan