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SCSI Terminology
It is important to understand some SCSI basics before adding drives to an MX-2424. The first step in this
understanding is familiarity with a few simple terms.
SCSI
Stands for Small Computer System Interface. This is the data transfer method and physical connection
used by the MX-2424 for connection to hard drives and backup solutions.
Throughput
This is the amount of data transferred from one device/component to another in a specified time period.
8-Bit Data Transfer
This refers to data transfer between a SCSI device and the MX-2424’s processors and supports
throughput of up to 20Mbytes/second. This should not be confused with the term “24-bit audio” which
refers to the resolution of recorded audio.
16-Bit Data Transfer
This refers to data transfer between a SCSI device and the MX-2424’s processors and supports
throughput of up to 80Mbytes/second. This should not be confused with the term “24-bit audio” which
refers to the resolution of recorded audio.
Ultra SCSI (Narrow)
This type of SCSI device uses 8-bit data transfers and generally employs a 50-pin connector. An example
of such a device would be the
DVD-GF2050
DVD-RAM drive, offered by TASCAM as a backup
solution for the MX-2424.
Ultra Wide SCSI
This type of SCSI device uses 16-bit data transfers and generally employs a 68-pin connector.
LVD (Wide Ultra2 SCSI)
Stands for Low Voltage Differential (also known as
Ultra2 SCSI
). This is the particular type of SCSI
protocol used by the MX-2424.
LVD SCSI
uses 16-bit data transfers and employs a High Density or
Very High Density 68-pin connector. This allows throughput of 80 Mbytes/second.
Low Voltage Differential (LVD) works by sending simultaneous pairs of data in a balanced
configuration. Just like a balanced audio signal, the noise is rejected when the signals are summed.
Because of noise rejection, the bus can operate at higher speeds and longer cable lengths. The MX
provides Ultra2/LVD performance on the internal and external bus.
SCSI Terminator
This is a special device that must be attached to the last device in a SCSI chain for the system to function.
SCSI ID
This is a number that is set on each SCSI device in a SCSI chain, which identifies that device to the MX-
2424.