ULTRA2 LVD SCSI HOST ADAPTER

Because the methods for terminating SCSI peripherals can vary widely, you should refer to a given peripheral’s documentation for instructions on how to enable or disable its termination. Here are some general tips about device termination, though:

Internal Ultra2 SCSI peripherals are shipped from the factory with termination disabled; this setting cannot be changed. Proper termination for internal Ultra2 peripherals is always provided by a built-in connector at the end of the attached internal Ultra2 SCSI cable.

On other kinds of internal SCSI peripherals, termination is usually controlled by manually setting a jumper or moving a switch on the unit, or by physically installing or removing one or more resistor modules on the unit.

On external SCSI peripherals of all kinds, termination is usually controlled by installing or removing a SCSI terminator, although some peripherals have internal termination that you can switch on or off instead.

Most non-Ultra2 SCSI peripherals come from the factory with termination enabled.

As it is shipped from the factory, your Ultra2 LVD SCSI Host Adapter can automatically enable or disable its built-in termination. If the Adapter senses that it is at the end of the bus—for example, if you attach only internal or only external SCSI devices to it—it will auto-terminate itself. If it senses that it is in the middle of the bus—for example, if you attach both internal and external SCSI devices to it— it will auto-disable its terminators.

If you would rather set the Adapter’s termination manually, you can go into the SmartSCSI™ Setup Utility in the Adapter’s firmware (see Section 4.6.4) and change the “SCSI Terminators” setting in the “Adapter Setup” menu. Switch from “Automatic” to either “ON” (always ON), “OFF” (always OFF), or a combination of “High bit ON”/“OFF” and “Low bit ON”/“OFF”:

Set the high bit and low bit both ON if the Adapter is at the end of the bus, so that only external devices or only internal devices are attached.

Set the high bit and low bit both OFF if the Adapter is in the middle of the bus, so that both internal and external devices are attached, and if at least one device on each side (internal and external) is a Wide SCSI (68-pin, 16-bit) device.

Set the high bit ON and the low bit OFF if the Adapter is in the middle of the bus, so that both internal and external devices are attached, and if all of the devices on either or both sides (internal and external) are Narrow SCSI (50-pin, 8-bit) devices.

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Black Box SCSI-2 LVD manual ULTRA2 LVD Scsi Host Adapter

SCSI-2 LVD specifications

The Black Box SCSI-2 LVD (Low Voltage Differential) represents a significant advancement in data storage and connectivity technology, particularly in environments requiring high performance and reliability. As a variant of the SCSI (Small Computer System Interface) standard, it is optimized for faster data communication, essential for modern computing needs.

One of the main features of SCSI-2 LVD is its capability to handle increased data transfer speeds compared to its predecessors. It supports a maximum data transfer rate of up to 80 MB/s, which is double that of the original SCSI-2 single-ended signaling. This increase in speed is largely due to the differential signaling that LVD employs, allowing for reduced electromagnetic interference and extended cable lengths while maintaining signal integrity. The technology effectively converts the SCSI bus into a more robust system that can accommodate various devices without compromising performance.

The SCSI-2 LVD standard is backward compatible, meaning that it can interface with older SCSI devices, albeit at reduced speeds. This compatibility is significant for users looking to upgrade their systems without discarding existing hardware. This makes SCSI-2 LVD an attractive choice for enterprise environments where legacy systems are common.

Another key characteristic is the flexible cabling options provided by SCSI-2 LVD. It can support cable lengths of up to 12 meters, which is beneficial for large data center configurations where space between devices can be substantial. This extended range does not typically come at the expense of performance, ensuring that data integrity remains high, even over longer distances.

In terms of technology, LVD employs lower voltage levels, which not only contributes to greater power efficiency but also minimizes heat generation in devices. This is particularly crucial in data centers where temperature management can impact hardware longevity and reliability. The combination of lower voltage use and differential signaling makes SCSI-2 LVD well-suited for high-density environments.

Error correction and handshaking features are also integral to SCSI-2 LVD, enhancing its robustness against data loss during transmission. These characteristics make it a reliable choice for applications requiring consistent and high-speed data access, such as server arrays and high-performance computing tasks.

Overall, Black Box SCSI-2 LVD stands out due to its impressive speed, compatibility, and extensive cabling options, positioning it as a reliable solution for demanding data environments. It effectively bridges the gap between legacy systems and modern technology, ensuring that users can optimize their data handling capabilities without significant disruption.