Computer system having system bus which couples adapter and processing units and requires acquisition for data transmission thereover

摘要

A data transmission system is provided in a computer system including at least one processing unit for processing data and at least one adapter for controlling a device coupled thereto, the processing unit and the adapter being coupled to each other by a bus, in which after information is forwarded to the bus from the processing unit or the adapter which has acquired use of the bus, the bus is released from the processing unit or the adapter. The data transmission system includes a plurality of buffers, provided in the adapter, for storing data to be transmitted to the processing unit, and a plurality of buffer control sequencers each of which are coupled to one of the plurality of buffers, each of the plurality of buffer control sequencers controlling transmission of data stored in a corresponding one of the plurality of buffers when use of the bus is granted to the relevant one of the plurality of buffer control sequencers in response to a request for permission to transmit data.