Patent ID: 8831131

Claim:
A method of data transfer by an asynchronous link, comprising: transmitting a data item from a sender to a receiver; receiving an acknowledgment signal in return from the receiver to the sender, wherein the data item and the acknowledgement signal are transmitted on an exchange conductor in at least three levels of potential, a first level of potential representing a first value of data item transmitted, a second level of potential representing an inactive potential level, and a third level of potential representing a second value of data item transmitted, wherein the acknowledgment signal is produced by the receiver by forcing the exchange conductor, by the receiver, to the inactive potential level, and the sender detecting said forcing of the exchange conductor; and in succession: forcing, by the sender of the data item, the exchange conductor to an active potential level; relaxing, by the sender of the data item, the forcing of the exchange conductor and the receiver detecting the active potential level; forcing, by the receiver, the exchange conductor to the inactive potential level, the switching of the exchange conductor from the active potential level to the inactive potential level constituting the acknowledgment signal; and relaxing, by the receiver, the forcing of the exchange conductor and the sender detecting the switching of the exchange conductor to the inactive potential level.