An apparatus and method thereof wherein a portable computer system or personal digital assistant generates a visual signal in response to an occurrence of a programmed event. For example, the portable computer system can use a light emitting diode to visually signal an alarm at a specified time. The visual signal can be varied in order to indicate the type of event associated with the alarm. In one implementation, the visual signal blinks at a particular rate depending on the type of event. In another implementation, the visual signal blinks a prescribed number of times or according to a particular pattern depending on the type of event. When enabled, the visual signal is generated in lieu of an audible signal, thus providing to the user a silent alarm that does not disturb other people in proximity, such as in a meeting, a theater, or some other gathering.