LSI manual Chapter Using the SYM8953U Host Adapter, General Description

Chapter 1

Using the SYM8953U

Host Adapter

This chapter describes the SYM8953U Host Adapter interface to PCI computer systems and includes these topics:

•Section 1.1, “General Description,” page 1-1

•Section 1.2, “Features,” page 1-2

•Section 1.3, “Interface Descriptions,” page 1-3

1.1General Description

The LSI Logic Corporation Symbios® SYM8953U PCI to Ultra2 SCSI Host Adapter board provides an Ultra2 SCSI interface to PCI computer systems. It is referred to as the SYM8953U throughout this guide. Installing this adapter in your PCI system allows connection of up to 15 SCSI devices.

The SYM8953U board is a 16-bit, Low Voltage Differential (LVD)/Single- Ended (SE) SCSI solution for your computer. This board also supports legacy Fast SCSI and Ultra SCSI devices, and the newest LVD Ultra2 SCSI devices. It is also backwards compatible with existing wide SCSI applications for the SYM8251S and SYM8751SP/E host adapters.

Symbios SCSI Device Management System (SDMS™) software operates the board. SCSI software provided by other vendors that works with the SYM53C895A chip can also be used. BIOS support for this adapter is incorporated on the board in a Flash memory device. The SYM8953U host adapter has a serial EEPROM device for storing the user’s SCSI bus configuration.

The SYM53C895A chip also contains a SCSI SCRIPTS™ processor that permits both DMA and SCSI commands to be fetched from host memory or internal SCRIPTS RAM. Algorithms written in SCSI SCRIPTS control

Symbios SYM8953U PCI to Ultra2 SCSI Host Adapter 1-1