The invention relates to contact memory cards (16) essentially comprising a memory (10) and its approach circuits (12, 14). The invention is characterized in that the approach circuits of the memory are modified (20) to allow for writing in or reading the memory (10) by means of electrical signals supplied by the terminal (18) in accordance with an asynchronous communication protocol with verification of the integrity of the transmitted codes. The signals received at the contacts (16) are analysed by the circuit (22) and then directed to the address register (26) and data register (28) by the switch circuit (24). The circuit (22) and the control circuit (14) transmit messages and codes to the terminal (18) by way of a transmission circuit (34).
