PURPOSE: To omit the need to decode the key data at the side of a host computer by arranging plural keys in the same display screen and seeting the code output formats such as the toggle, the repetition, at every key to transmit these set formats to a host computer.

CONSTITUTION: A touch sensor 1 can detect the touch positions on a display device and simultaneously is divided into minor areas R1 - R3. A minor area table 6 decides previously the output forms of the key information in response to the areas R1 - R3. A means 5 decides one of the areas R1 - R3 that includes a touch position detected by the sensor 1. Simultaneously, one of areas R1 - R3 that includes the coordinates detected by the sensor 1 is collated with the table 6 for the decision of the output format of the key information and the key information is transmitted via a transmission control means 5. That is, one of areas R1 - R3 is decided according to the touch position on the display device, and the output format of the key information is decided based on the decided area. As a result, plural types of key arrangements K1 - K3 can be applied on the same screen without giving the load to a communication interface part 7 and a host computer 5.