ULTRA2 LVD SCSI HOST ADAPTER

Enable Disconnect: When this option (usually referred to as “disconnect/ reconnect”) is set to “Yes” (the factory-default setting), devices can temporarily disconnect from the SCSI bus to allow the Adapter to perform other functions on the bus. The device and the Adapter can then reconnect when the bus is needed. We strongly recommend that you not set this option to “No” unless the corresponding device is an older one that cannot support disconnect/reconnect.

Enable Wide Negotiation: This option determines whether or not the Adapter will start data-transfer negotiations with the corresponding device by requesting a “wide SCSI” (16-bit) path. Set this option to “No” for any narrow-only device or for any other attached device that doesn’t seem to handle wide data transfer properly (as is often the case with certain older CD-ROM, recordable CD, and tape drives). The factory-default setting for this option is “Yes.”

4.6.4THE ADAPTER SETUP MENU

If you select “Adapter Setup” at the Main Menu and press ENTER, the Utility displays a screen at which you can set three key options for the Ultra2 LVD SCSI Host Adapter itself. Use the up- and down-arrow keys to select an option, the plus and minus keys to change its setting, or <F8> to reload the factory-default settings for all options.

Host Adapter SCSI ID: If necessary, you can use this option to change the Adapter’s ID number on the SCSI bus. The Adapter supports sixteen IDs numbered 0 through 15. ID 7 (the Adapter’s factory-default ID) has the highest boot priority (is examined first during the boot process); from there, IDs are examined in numeric order from 0 to 15. This means that if you have to change the Adapter’s ID, you should make it as low a number as possible.

You can have multiple SCSI host adapters attached to the same SCSI bus (see Section 4.5); these must all have different SCSI IDs. But if you have multiple Adapters that are each attached to separate SCSI buses, even if they’re installed on the same PCI bus, you don’t have to use different SCSI IDs for the Adapters.

SCSI Terminator: You can use this option to have the Adapter auto-terminate itself (“Automatic,” the factory-default setting) or—if the Adapter doesn’t seem to autosense the bus state properly, or if for whatever reason you would rather set termination yourself—set its termination always “ON” (if the Adapter is at the end of the bus) or “OFF” (if the Adapter is in the middle of the bus), or set the termination to the proper combination of “High bit ON”/“OFF” and “Low bit ON”/“OFF” as described in Section 3.4.

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Black Box SCSI-2 LVD manual Adapter Setup Menu
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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.
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