Rear Panel Connections; Scsi Connections; Notes Regarding Scsi - Akai DD1500 User Manual

REAR PANEL CONNECTIONS

The DD1500x's rear panel consists of two SCSI ports plus provision for two cooling fans.
The SCSI ports are 50-way Amphenol connectors (i.e. standard SCSI connectors!) and
connect to the DD1500m's SCSI port The sockets are wired as 'thru' connections so if you
wish to connect one or more extra drives, connect them to the unused port. I.e.:
As shown in the diagram, please pay particular attention to the termination of each drive.
Failure to do so will result in erratic performance, even loss of data.
1. The devices at each end of the SCSI chain MUST be properly terminated. The
DD1500m is terminated internally and so you need not worry about that. The
DD1500x has a DIP switch that allows you to turn termination on or off for each drive it
may have. If you are using just one drive, then that should be terminated. If you are
using two drives, the first drive should be un-terminated and the second drive must be
terminated.
Please see the next page for details on termination on the DD1500x. If the drive you
are using is not a DD1500x, you must consult the device's owner's manual.
Akai cannot guarantee the performance of drives other than those recommended and
cannot accept liability for any problems you may experience with untested drives.
2. The total length of the whole SCSI chain must not exceed 6 metres otherwise you will
get unpredictable performance, maybe even corruption of data. Please note that this
refers to the TOTAL LENGTH of the chain, not the individual cables between each
SCSI device.
3. Every SCSI device must have a unique SCSI ID number otherwise you will have
problems as devices clash on the SCSI buss. For example, if two drives have an ID of
1 and the DD1500m sends out a message "PLAY THE RECORDING TAKE 3 ON THE
DISK IN SCSI DEVICE#1", the system will fail because it will be trying to access both
the drives looking for TAKE 3 and not know which it should choose. This is a common
problem of all SCSI devices and is not a fault with the DD1500.
The DD1500 system can accommodate up to seven disk drives and it is good practice
to set the SCSI IDs sequentially so you can keep track of things more easily (i.e. first
drive ID#0, second drive ID#1, third drive ID#2, etc.).
NOTE: If the drive you are using is something other than a DD1500X, then it is likely that it
will have two SCSI ports for 'daisy-chaining' devices as shown above.
Version 2.00 - March, 1996
DD1500m

** NOTES REGARDING SCSI **

CONNECTIONS - DD1500X - 4
Terminated
Unterminated
Unterminated
Terminated
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