• Internal and external SCSI connectors• Initiator and target modes of operation fully supported• Differential SCSI (AHA-1744 only)• SCSI-1 and SCSI-2 compatible• Tagged queuingBoard FeaturesIn addition to extensive functions on the two main interfaces of the board, the intelli-gence built into the board microcode and BIOS software allows a number of addi-tional functions to be offered, including:• Scatter/Gather operation• Boot from any target (set as configuration option)• Compatible with existing AHA-1540 family driver software (ASW-1400 seriesmanagers)• True multithreaded operation supporting up to 255 tasks simultaneously• Programmable mailbox architecture• Bootable BIOS for standard hard disk emulation• Floppy Diskette Controller (AHA-1742A only)While all versions of the board fully support all of the above features, they are distin-guished by:• AHA-1740A Fast SCSI-to-EISA Host Adapter• AHA-1742A Fast SCSI-to-EISA Host Adapter with floppy diskette controller• AHA-1744 Fast differential SCSI-to-EISA Host AdapterThe AHA-1740A/1742A/1744 microcode is available in two separate versions which co-exist simultaneously in the onboard PROM, but must be configured into one of thetwo available modes:• Standard Mode• Enhanced ModeThe modes cannot operate simultaneously. The EISA Configuration Utility (ECU)must be run to select one of the modes (Refer to Chapter Three, Installation). TheEISA-to-Fast SCSI Host Adapter Introduction1-3
