| 摘要 |
The present invention is useful in a data processing system having a data processor coupled to a SCSI channel disposed for transmitting and receiving data between the data processor and a peripheral storage subsystem. The present invention is a method for controlling a bridge controller that permits expanding the maximum allowable number of disk drives connectable to the SCSI channel. In particular the method comprises the steps of receiving a command from the SCSI channel; initializing queue pointers from a memory in response to the command; determining the command type and setting flags and pointers in response thereto; when the command is a write operation, transferring data from the SCSI channel and storing the data in the memory; selecting a disk drive to receive the data by sending message and command bytes to the disk drive; and, transferring the data from the memory to the selected disk drive. The method of the present invention also includes the steps of transferring data from the disk drive and storing the data in the memory when the command is a read command, selecting a SCSI channel to receive data by sending message bytes to the SCSI channel, and transferring the data from the memory to the selected SCSI channel.
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