Переходник DEC SYM20101 SCSI converter board (SCSI Bus Expander/Extender Board supports Single-Ended(SE)-to-SE or SE-to-Differential mode)

Описание и характеристики

Single-ended to Single-ended Ultra SCSI Bus Expander Board
Improved reliability with a single chip solution Does not consume a SCSI ID, completely transparent to the SCSI subsystem The SCSI signals are re-timed as needed to guarantee or improve the required SCSI timings. Precision delay control block guarantee specified timings such as output pulse widths, setup times and hold times. Complete support for SCSI -1, -2, and -3 Completely independent of software
Benefits
Ideal for cluster configurations for availability and scalability Electrically isolates SCSI buses Complete board solution for quicker time-tomarket Expands device connectivity and cable distances in certain applications Allows for large disk configurations
SYM20101 Ultra SCSI Bus Expander Board
Plug-andPlay Yes
Bus Interface Two SCSI to SCSI
SCSI Rate 40 MB / s Synchronous 14 MB / s Asynchronous Fast / Ultra SCSI
SCSI Bus 16-bit Single-Ended to / from Single-Ended
SCSI Connectors (2) 68-pin
Features
Termination-enable control Termination power supplied through self resetting current limiting device Termination power control Connectors for off-board SCSI active LEDs and termination enable control Supports wide Ultra SCSI 40 MB / s synchronous transfer rate Accepts any asynchronous or synchronous data transfer rates up to Ultra SCSI Targets and initiators can be located on either the SCSI A or B side Supports TolerANT® active negation technology
When the switches are ON, termination power is supplied to the on-board terminators and to TERMPWR on the cable from the board. When the switches are OFF, only TERMPWR from the cable is used to power the terminators. One LED per side indicates that TERMPWR is shorted to ground.
SCSI Busy
The board contains an LED per side which indicates when a SCSI is active on that side. Also, an LED interface (J4) allows an external LED harness to be connected to the board for external mounting of SCSI busy LEDs.
Hardware Specifications
Technical Description
Termination Control
To aid the subsystem designer, the on-board active SCSI terminators can be controlled by either switches (SW3 & SW4) or the pin connector (J5). To disable the on-board active SCSI terminators, SW3 (A) & SW4 (B), or external switches on the subsystem cabled to J5, should be ON. Figure 2 shows the locations of these switches and pin connectors.
Termination Power
Termination power can be supplied to or from the cable. Switch SW1 controls Side A, while switch SW2 controls Side B.