Extension module for remote computer terminal

摘要

The external extension module is intended to be used with an interactive computer terminal. It comprises a pluggable connector on the terminal for setting up links with the bus of the terminal and electric power supply source in the terminal. The module comprises at least one random-access memory box with reading and writing 12 and an interface for adapting to the bus of the terminal. The box moreover comprises a local source 18 supplying a voltage which is sufficient to preserve the information contained in the box and means for preventing writing in the said box when the power supply voltage is lower than a predetermined value. <IMAGE>