The AHA-1744 microcode is stored in an EEPROM. This allows
the microcode to be changed with the Adaptec
adl.exe
program.
The
adl.exe
program can also be used to determine the checksum
of the currently installed microcode and low-level format SCSI
fixed disks. Both the standard and enhanced mode microcode can
reside in the EEPROM at the same time.
The AHA-1740A/1742A uses an EPROM for the microcode, which
does not allow the microcode to be changed. However, the
adl.exe
program can still be used to low-level format fixed disk drives.
The AHA-1740A/1742A/1744, like all EISA I/O cards, do not have
jumpers to change various configuration options. These options
are changed via the EISA Configuration utility provided with
every EISA system. The AHA-1740A/1742A/1744 does have a
jumper that is used to determine whether or not the host adapter
will supply terminator power to the SCSI bus. In addition, the
AHA-1742A has a jumper that is used to enable or disable the
on-board floppy controller.
The AHA-1740A/1742A/1744 can be used to install up to 7 SCSI
devices. Up to 56 devices can be installed if bridge controllers are
used; however, this is not usually done.
The AHA-1740A/1742A/1744 supports processor target mode,
which allows the host adapter to be an initiator and a target. The
use of processor target mode is fully documented in the AHA-
1740A/1742A/1744 Technical Reference Manual.
EISA-to-Fast SCSI Host Adapter Overview
1-3