IBM NetVista, Техническое руководство

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8
NetVista™ Technical Information Manual
Features provided by USB technology include:
• Support for hot-pluggable devices
• Support for concurrent operation of multiple devices
• Suitability for different device speeds
• Support for cable length of up to five meters (16 ft. 5 in) from host to hub or from
hub to hub
• Wide range of packet sizes
• Limited power to hubs
For information on the connector pin assignments for the USB interface, see “USB
port connectors” on page 29.
Super I/O controller
Control of the integrated I/O and diskette drive controllers is provided by a single
module. This module, which supports Plug and Play, controls the following features:
• Diskette drive interface
• Serial port
• Parallel port
• Keyboard and mouse ports
• MIDI/joystick port (A20 models only)
Diskette drive interface
The NetVista computer diskette drive subsystem supports the following devices:
• 1.44 MB, 3.5-inch diskette drive
• 1.44 MB, 3.5-inch 3-mode drive for Japan (no BIOS support for 3-mode drive)
• 1.2 MB, 5.25-inch diskette drive
• 1 Mbps, 500 Kbps, or 250 Kbps internal tape drive
Note: A 2.88 MB 3.5-inch diskette drive is not supported.
One 34-pin connector is provided on the system board for diskette drive support. For
information about the connector pin assignments, see “Diskette drive connector” on
page 32.
A setting in the Configuration/Setup Utility program enables or disables diskette write
protection.
Serial ports
Two UART serial ports are integrated into the system board of A40 and A40p models.
A20 models come with one serial port. The serial ports include 16-byte, first-in first-out
(FIFO) buffers and have programmable baud rate generators. The serial ports are
NS16450 and PC16550A compatible.
For information on the connector pin assignments, see “Serial connector” on page 30.
Note: The current loop interface is not supported.
The following figure shows the default serial port assignments in the configuration.