UPGRADING REPAIRING PCs

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Chapter 6—Serial Ports and Modems
Pinouts for External Modem Cable (9-Pin at PC)
For most external modems, you need an RS-232 modem cable,
which will have a 9-pin connector on one end and a 25-pin connector
on the other end. Because RS-232 is a flexible standard
encompassing many different pinouts, be sure the cable is constructed
according to the following diagram:
1. PC (with 9-pin COM port - male)
Modem (25-pin port - female)
3 TX data 2
2 RX data 3
7 RTS 4
8 CTS 5
6 DSR 6
5 SIG GND 7
1 CXR 8
4 DTR 20
9 RI 22
2. If you purchase an RS-232 modem cable pre-built at a store,
you’ll have a cable that works with your PC and your
modem. However, you can use the preceding chart to build
your own cable or, by using a cable tester, determine whether
an existing RS-232 cable in your office is actually made for
modems or some other device.
Win98SE, Windows 2000, Windows
Me, and ICS
Windows 98 Second Edition, Windows 2000 Professional, and the
new Windows Millennium Edition (Windows Me) all feature a
built-in gateway program called ICS (Internet Connection Sharing),
which allows users to share a single dial-up, ISDN, cable modem, or
xDSL connection. Win98SE, Windows Millennium Edition, and
Windows 2000 Professional can be purchased as an upgrade to
older versions of Windows, and users of the original version of
Windows 98 can purchase a CD-ROM from Microsoft that will
upgrade the original version to the Second Edition.
Because ICS is a gateway and clients use TCP/IP networking to use
the gateway, only the gateway computer needs to use Win98SE,