| 摘要 |
<p>A serializer/deserializer interfacing a keypad or keyboard to a processing system is illustrated. In one application, the processor is arranged to generate keypad scan and input keypad sense lines directly. However, to minimize wires on intervening cables, a serializer and deserializer is inserted between the processor system, the serializer/deserializer forming a virtual keypad. In this case, the processor scans the deserializer as if it were the keypad and the keypad is scanned by the serializer as if it were the processor. However, the serializer converts the scanning of the keypad into a serial bit stream that is sent to the deserializer using only a data line and a clock line. The deserializer accepts the serial bit stream and reconfigures the data into a response that mimics the response of the physical keypad as the computer system scans the virtual keypad, the deserializer. In one embodiment an actual second keypad is formed in the deserializer and activated as the first keypad is activated, wherein the computer scans the second keypad in the usual fashion.</p> |
