Programmable, multi-buffer device and method for exchanging messages

Abstract

The invention pertains to the information systems field, in which a system is constituted by several machines which, in order to exchange data, communicate with one another through serial links. The invention relates more specifically to a device for exchanging messages between two data processing machines by means of a bidirectional serial link (2). In each machine, the device comprises a first outgoing buffer memory (20) for containing only request-type messages to be sent through the bidirectional serial link (2), a second outgoing buffer memory (21) for containing only response-type messages to be sent through the bidirectional serial link (2), a first incoming buffer memory (22) for containing only request-type messages received from the bidirectional serial link (2), a second incoming buffer memory (23) for containing only response-type messages received from the bidirectional serial link (2), a first switching unit (24) which authorizes the transfer of a message from the first outgoing buffer memory (20) or from the second outgoing buffer memory (21), respectively, to the bidirectional serial link (2) when a first incoming buffer memory (32) or a second incoming buffer memory (33), respectively, of the second machine has sufficient space to receive said message, and a second switching unit (25) which transfers the request-type messages or the response-type messages, respectively, received from the bidirectional serial link (2), to the first incoming buffer memory (22) or the second incoming buffer memory (23), respectively.