OAK SCSI 4, Руководство пользователя

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inability of the initiating system to deal with such high data transfer
rates. Using an Archimedes with the Oak SCSI controller card avoids
this degradation of performance. The Oak card buffers the 8 bit data
from the SCSI bus in order to perform 16 bit memory transfers to and
from the Archimedes, thereby vastly reducing the normal handshaking
overhead.
SCSI imposes no restrictions on the numbers of any particular type of
device (up to a maximum of 7) on the SCSI bus; however, the Filecore
module within Risc OS allows a filing system (SCSIFS in the case of
the Oak SCSI controller card) to have only 4 winchesters, and also
limits the capacity of each winchester to 512Mb. Thus a total of 2
gigabytes of winchester storage is achievable under the SCSIFS filing
system.
Non-winchester SCSI devices (e.g. tape streamers, CD ROMs) may
also be addressed by the Oak SCSI controller card via SWIs which
allow low level access to SCSI commands, or via high level software
available separately such as the !OakTape tape backup software from
Oak.
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