Hu430 Nlx Motherboard User Guide 124575Ug Revision; Keyboard And Mouse; Floppy Disk Interface; Serial Ports - Mitsubishi Electric Hurricane HU430 User Manual

HU430 NLX Motherboard User Guide 124575UG Revision 2
scheme compatible with that of the PIIX4. This allows a wide selection of interrupt channels
for the serial and parallel ports, and the floppy disk controller.

2.7.1 Keyboard and Mouse

This is implemented in an SMC 37C675 device on the motherboard. The keyboard and mouse
controller uses the Phoenix Multikey version 1.40 firmware. PS/2 style keyboard and mouse
ports are provided on the rear panel. This version does not support keyboard/mouse port
swapping.

2.7.2 Floppy Disk Interface

This is implemented in an SMC 37C675 device on the motherboard. Standard 2-mode and 3-
mode 3½" drives are supported. The 3-mode drive includes the 1.6MB (unformatted) mode
that is popular in Japan; this requires a special OS device driver that installs the 1.6MB mode
floppy disk drive as another system device.
The floppy disk drive signals are routed from the motherboard to the NLX riser and the
floppy disk drive connector is mounted on the NLX riser.
As per the NLX specification, all floppy disk input signals to the motherboard must be pulled
up on the NLX riser.

2.7.3 Serial Ports

This is implemented in an SMC 37C675 device on the motherboard. There are two standard
COM ports which are wired to two standard 9-way D-type connectors on the rear panel. The
maximum Baud rate is 115K bits per second.

2.7.4 Parallel Port

This is implemented in an SMC 37C675 device on the motherboard. This is EPP 1.7/1.9 and
IEE1284 (ECP) compliant and is compatible with a standard (output only) PC parallel port as
well as a bi-directional (PS/2 style) parallel port. There is a 25-way D-type connector on the
rear panel.

2.8 Additional I/O

2.8.1 IDE Disk Controller

This is integrated into the PIIX4E South Bridge device. Two connectors are provided on the
NLX riser allowing two drives per cable. The system BIOS auto-detects the drives fitted and
sets the best signal timing appropriate for the drives. PIIX4E supports up to PIO mode 4
timing and bus master IDE transfers up to 33MBps (ATA33). The total cable length attached
to each connector must not exceed 12" or signal integrity problems may result.
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