CHAPTER 5: Driver Installation

5.1.4THE ASPI REMOVABLE-DISK DRIVER AND ITS COMMAND LINE OPTIONS

INIDISK.SYS is a DOS “block” device driver for supporting SCSI fixed disks, removable disks, and MO (magneto-optical) devices. INIDISK.SYS requires that the Ultra2 LVD SCSI Host Adapter’s ASPI Manager be loaded. A “DEVICE=” or “DEVICEHIGH=” command line to load INIDISK.S'YS is automatically added to the CONFIG.SYS startup file by the DOSSETUP program. (You will be asked whether or not you want to load this driver high; the program will add the correpsonding command to CONFIG.SYS depending on how you answer.) INIDISK.SYS is on Driver Disk 1. It has three command-line options—/R, /T, and /X:—as described below.

/R or /r—This option specifies the number of logical drives to reserve for MO and removable-disk devices. MO and removable-disk media are capable of being partitioned just like a fixed disk. For every DOS partition on the medium, a logical DOS drive letter needs to be available. INIDISK.SYS will support as many logical drives as required (up to the maximum supported by DOS), based on the partitioning of the medium that is present when your system boots. However, the medium may be removed at any time and a new disk may be inserted. The new disk may have more (or fewer) partitions then the original disk.

Use this option to reserve drive letters at startup in order to make it possible to swap in a disk with more partitions than the original disk present at boot time had. The value after the /R or /r determines how many drive letters will be reserved per device. For example, if the user specifies /R4 and there are two devices attached to the SCSI bus, then a total of eight drive letters will be reserved.

/T or /t—Use this option to specify a timeout value to be used when sending commands to a SCSI drive. If a SCSI drive does not respond to a command within the specified timeout period, the command will be aborted and an appropriate error message will be displayed. The timeout value is specified in minutes. Valid values are “1” (one minute) through “9” (nine minutes) and “D” or “d” (timeout disabled). We do not recommend disabling the timeout—if you do, faulty hardware will be able to lock up your system. Examples of valid command-line phrases:

/T4

/Td

/TD

/T1

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Black Box SCSI-2 LVD manual Aspi REMOVABLE-DISK Driver and ITS Command Line Options

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.