LSI SYM8953U manual On-Board LED

integration of I/O transceivers into the chip. LVD provides the reliability of HVD SCSI without the added cost of external differential transceivers. Ultra2 SCSI with LVD allows a longer SCSI cable and more devices on the bus, using the same cables defined in the SCSI-3 parallel Interface (SPI-2) standard for Ultra SCSI.

Important: To utilize Ultra2 SCSI performance, you must only have LVD devices on the bus. Do not mix any SE devices with LVD devices or the entire bus will drop to SE, limiting bus performance to Ultra SCSI levels.

1.3.5 On-Board LED

An on-board LED (CR1) indicates the status of the SCSI bus. This SCSI Activity LED lights when the SCSI bus is transferring information. It is located near J4 (see Figure A.1).

1-6 Using the SYM8953U Host Adapter