We should test how accurately our stopwatch keeps time. To do this, let's use a second microcontroller to press the start button on a stopwatch, wait a precise amount of time and then press teh stop button. The LCD should show the same precise value every time.
By "press a button", I imagine it like this. When a button is really pressed, it triggres an interrupt on a port (button 1 is on register 1.2, meaning the second register of port 1 for example). But, the interrupt occurs when a change is sensed on any of the registers in the same port - so let's send an electrical signal to tone of the GPIO pins on the board and use that to trigger exactly the same interrupt as a button press.
We should test how accurately our stopwatch keeps time. To do this, let's use a second microcontroller to press the start button on a stopwatch, wait a precise amount of time and then press teh stop button. The LCD should show the same precise value every time.
By "press a button", I imagine it like this. When a button is really pressed, it triggres an interrupt on a port (button 1 is on register 1.2, meaning the second register of port 1 for example). But, the interrupt occurs when a change is sensed on any of the registers in the same port - so let's send an electrical signal to tone of the GPIO pins on the board and use that to trigger exactly the same interrupt as a button press.