Aha-1740A/1742A/1744 Product Features; Eisa Features; Scsi Features - Adaptec AHA-1740A Technical Reference Manual

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AHA-1740A/1742A/1744 Product Features

EISA Features

The AHA-1740A/1742A/1744 is a full-performance EISA board offering the highest
performance available across the bus. It takes advantage of first-party DMA opera-
tions, also known as bus mastering, which allow data transfers to proceed at high
data rates without system processor intervention. The main EISA functions which
come standard on the board include:
Auto Configuration Support
High-performance Bus Master transfers with burst cycles which provide a
data rate of 33 MBytes/second
32-bit data path
32-bit address space
Even or odd starting address and byte count handling
1K FIFO for efficient data transfer
Interrupts enabled/disabled through I/O port write
Interrupts configurable for either edge or level trigger
Dual Control Interface, AHA-1540 family-compatible (Standard Mode) or
EISA-SCB compatible (Enhanced Mode)

SCSI Features

Adaptec has long been a supplier of leading edge SCSI products and the AHA-
1740A/1742A/1744 is no exception. The board uses industry-standard protocol ICs
which fully comply with the 1990 ANSI SCSI specification, including:
Maximum synchronous SCSI transfer rate of 10.0 MBytes/second (Fast SCSI)
Asynchronous and synchronous peripherals supported simultaneously
Disable synchronous negotiation independently on each target as a configura-
tion option
Disable disconnection independently on each target as a configuration option
Supports Modify Data Pointer message (Zero Latency Reads)
High-density SCSI-2 connector
Non-destructive current limit on terminator power supply
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AHA-1740A/1742A/1744