− | This means that when signal 1 gets active(button press), a capital A will be sent to the serial port. A lowercase 'a' will be sent when the signal is deactivated(button release). Mechanical buttons can be connected directly. | + | This means that when light falls on the sensor, a capital A will be sent to the serial port. A lowercase 'a' will be sent when the signal is deactivated(no light). |