Lenovo PC 300GL Understanding Your Personal Computer 6267, 6277, 6287 - Page 27

Universal Serial Bus Ports, PC 300GL User Guide

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2E8 The available IRQs are: IRQ 4 IRQ 3 IRQ 9 IRQ 10 IRQ 11 IRQ 14 IRQ 15 There is no direct relationship among the port connectors, the available port settings, and the COM numbers. When you start the computer, the power-on self-test (POST) assigns COM numbers to the port addresses that are actually in use at the time. POST goes down the list of addresses sequentially to assign COM numbers to each address in use by a serial device. If an address is not in use, a COM number is not assigned to it. POST assigns the next available COM number to the next address in use, if any. You can view the port address and IRQ settings for serial ports using the Configuration/Setup Utility Program. You will not see the COM numbers on the setup screens. To see port settings and COM assignments for all serial ports, you can use one of the diagnostic programs available with the IBM-preinstalled software package. Generally, you do not have to change serial-port settings. However, if you add a serial adapter or use special hardware or software that causes a configuration conflict, you might have to change port settings. If so, you can change the settings for the serial port using the Configuration/Setup Utility Program. Refer to the PC 300GL User Guide for more information about using the Configuration/Setup Utility Program. To connect a device to your serial port, use a serial cable (purchased separately) to connect the device to the serial connector at the back of the computer. Refer to the documentation that comes with your I/O device for specific installation instructions. Universal Serial Bus Ports Universal serial bus (USB) is an emerging serial interface standard. The USB port is a connector for devices that previously used serial, parallel, keyboard, mouse, and game ports. USB technology uses Plug and Play features to determine what device has been connected to the port. Each USB device is accessed by a unique USB address. A device called a hub is used to convert a single USB connector into multiple attachment points. A hub has multiple ports where devices can be attached. USB operates up to 12 megabits-per-second (Mbps) and supports a maximum of 127 devices. I/O Features 19

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2E8
The available IRQs are:
IRQ 4
IRQ 3
IRQ 9
IRQ 10
IRQ 11
IRQ 14
IRQ 15
There is no direct relationship among the port connectors, the available port settings, and
the COM numbers.
When you start the computer, the power-on self-test (POST) assigns
COM numbers to the port addresses that are actually in use at the time.
POST goes down
the list of addresses sequentially to assign COM numbers to each address in use by a serial
device.
If an address is not in use, a COM number is not assigned to it.
POST assigns the
next available COM number to the next address in use, if any.
You can view the port address and IRQ settings for serial ports using the
Configuration/Setup Utility Program.
You will not see the COM numbers on the setup
screens.
To see port settings and COM assignments for all serial ports, you can use one of
the diagnostic programs available with the IBM-preinstalled software package.
Generally, you do not have to change serial-port settings.
However, if you add a serial
adapter or use special hardware or software that causes a configuration conflict, you might
have to change port settings.
If so, you can change the settings for the serial port using the
Configuration/Setup Utility Program.
Refer to the
PC 300GL User Guide
for more
information about using the Configuration/Setup Utility Program.
To connect a device to your serial port, use a serial cable (purchased separately) to connect
the device to the serial connector at the back of the computer.
Refer to the documentation
that comes with your I/O device for specific installation instructions.
Universal Serial Bus Ports
Universal serial bus (USB)
is an emerging serial interface standard.
The USB port is a
connector for devices that previously used serial, parallel, keyboard, mouse, and game
ports.
USB technology uses Plug and Play features to determine what device has been
connected to the port.
Each USB device is accessed by a unique USB address.
A device
called a
hub
is used to convert a single USB connector into multiple attachment points.
A
hub has multiple ports where devices can be attached.
USB operates up to 12
megabits-per-second (Mbps) and supports a maximum of 127 devices.
I/O Features
19