Parity Check / Crc Check - Dawicontrol DC-29160 U3W Mode D'emploi

Manual
Your Dawicontrol SCSI host adapter supports both kinds of data transmission.
Most SCSI devices supporting synchronous data transmission automatically request
the synchronous mode from the host adapter. By appropriate settings in the SCSI set-
up the host adapter can be told to automatically activate synchronous data transmission
with certain SCSI devices. In this case, a corresponding message is transferred to the
SCSI device with every "inquiry" and "request sense" SCSI command. Similarly,
synchronous data transmission can be prevented for certain SCSI devices by the SCSI
set-up, even if the corresponding device automatically requests the synchronous
mode.

5.2. Parity Check / CRC Check

The SCSI interface carries out a parity check of data for data being transmitted
from the host adapter to the device or vice versa. Every single transmitted byte is
checked; therefore, a repeated transmission can be requested in case of an error. With
many SCSI devices, parity check can be switched on or off (mostly by a jumper). If
parity is switched off, only incoming data is not submitted to parity check; outgoing
data is still secured by a parity bit. Furthermore, there are still some devices featuring
no parity check at all. Your Dawicontrol SCSI host adapter automatically recognizes
which connected devices support parity check and then individually adjusts parity
support for every device.
In U160 mode, a CRC check is carried out instead of a parity check, which offers
even higher data security. The CRC check secures every transmitted data block by
means of a checksum.
5.3. Power Management of SCSI Drives
Your Dawicontrol host adapter offers you the possibility of having all kinds of
rotating storage media (hard disk, disk cartridge and CD-ROM drives) switched off
automatically if the drives concerned have been inactive for some time.
In case of renewed access the respective drives are automatically booted up
again. This enables you to save energy in a simple way and to reduce noise pollution
at your place of work considerably. Basically, the power save function is activated by
the parameter "PS=.." by indicating the maximum duration of inactivity intended for
the drives. Renewed access to the drives concerned will restart time measurement.
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