Asynchronous memory card
AssigneeGemplus
InventorsPascal Cooreman, Stephane Rayon, Bertrand Gomez
Life of this patent
Estimating the term…
Abstract
A memory card fitted with contacts contains a memory and its access circuits. The memory access circuits are modified to allow recording or reading the memory via electric signals supplied by a terminal according to an asynchronous-type communication protocol with integrity check of the codes transmitted. The signals received on the contacts are analysed by an analysis circuit, then switched to address and data registers by a switch circuit. The analysis circuit and a control circuit transmit messages and codes to the terminal via a transmission circuit.
Claims8
A memory card, consisting essentially of:
- contacts for communicating with a terminal external to said card;
- a memory storing data that is transferred between the card and a terminal;
- address and control circuits that control the reading and writing of data from and to said memory;
- a signal receiving circuit that receives instruction signals from a terminal, generates messages in response to receipt of the instruction signals, and forwards codes contained within said instruction signals;
- an address register associated with said address circuit that stores address codes forwarded by said signal receiving circuit;
- a data register that stores control codes and data codes forwarded by said signal receiving circuit;
- a detector circuit that receives codes forwarded by said signal receiving circuit and selectively directs said codes to one of said registers;
- an output register that receives data read from said memory;
- and
- a transmission circuit that supplies data from said output register and messages generated by said signal receiving circuit to said contacts for transmission to a terminal.
A memory card, comprising:
- contacts for communicating with a terminal external to said card;
- a memory storing data that is transferred between the card and a terminal;
- address and control circuits that control the reading and writing of data from and to said memory;
- and
- a data transfer system connecting said contacts to said address and control circuits that transfers data contained within signals received from a terminal to said address and control circuits for storage in said memory, and transfers data read from said memory to said contacts, without using a CPU to effect such transfers.
Dependencies are inferred from the claim text.