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- Path: pathway1.pathcom.com!ts2l16
- From: insystem@pathcom.com (Geoffrey Welsh)
- Newsgroups: comp.dcom.modems
- Subject: Re: Why this UART struggle?
- Date: 11 Feb 1996 19:49:00 GMT
- Organization: InSystems Technologies Inc.
- Message-ID: <4flh7c$mv5@pathway1.pathcom.com>
- References: <4fgdgh$lbt@news.flinet.com>
- NNTP-Posting-Host: ts2l16.pathcom.com
- X-Newsreader: News Xpress Version 1.0 Beta #4
-
- In article <4fgdgh$lbt@news.flinet.com>, kristof@flinet.com wrote:
- >Reading some of the articles about UART chips and
- >struggles to make the right upgrades with the right cards
- >I am wondering what is the advantage of having them
- >(like the new ones 16550A) for modems in the first place?
- >They are only needed for an external modem.
- >Just stick an internal modem into an ISA slot which exists on
- >any PC and just forget this UART business.
- >All the 28.8 or 33.6kbps have UART built-in (or rather
- >chips which just emulate it). The internal modems are cheaper,
- >take no extra space and do exatcly the same job.
- >
- >Am I missing something here?
-
- Yeah: PC-internal modems aren't for everyone. One of my previous rants on the
- topic follows.
-
- Newsgroups: comp.sys.ibm.pc.hardware.comm,comp.dcom.modems
- From: geoff@zswamp.UUCP (Geoffrey Welsh)
- Subject: Re: Why does nobody like internal modems
- Date: Sun, 28 Jan 1996 13:34:00 EST
-
- Stefano Mosca <fly@rm3.flashnet.it> writes:
-
- > I have a 28.8k internal modem and looking around
- > it seems that everybody prefers external modems,
- > why??????
-
- They're not for everyone, and an internal may be fine for you... but some of
- us prefer externals because:
-
- ... the activity LEDs on external modems are indispensible status and
- diagnostic tools, and some modems (such as USR) even have convenient external
- volume controls. I don't even like using the volume dial on the back of a
- Sound Blaster card... not that most PC-internal modems have one anyway.
-
- ... external modems don't impose much of a load on the PC's power supply, and
- neither contribute to the heat inside the case nor malfunction because of the
- heat generated by other PC components.
-
- ... external modems don't force you to use the CPU-intensive and speed-
- limited interface of a UART (or something mimicking a UART); with an external
- modem, you can use anything from a little 230,400 bps two-port Hayes
- intelligent serial card to a 224-port Digiboard card.
-
- ... you can't plug PC-internal modems into other computers, and that doesn't
- even take such things as MicroChannel or PCI slots into account. I've plugged
- my external modems into everything from a Commodore 64 through an AT&T 3B4000
- minicomputer. Multiport serial cards, terminal servers, etc., _require_
- external (or rackmount) modems.
-
- ... you can't put more than a couple of PC-internal modems into a single PC.
-
- Even my home PC has two very different modems plugged in (which I could have
- done internally, I suppose, because I went SCSI and avoided internal
- everything else so I have lots of slots free... friends who bought internal
- modems, sound cards, proprietary interface CD-ROMs and tape drives, etc. are
- out of slots with only one modem; some can't even upgrade their motherboards
- because most new boards have only seven slots in stead of eight, or have fewer
- AT slots to make room for PCI slots, or have some 8-bit connectors).
-
- ... internal modems can't be reset without resetting the whole computer. If
- it's a desktop computer owned by an individual for surfing the 'net, that's a
- minor inconvenince to one person (it takes longer to reboot than to switch the
- modem off and on). If it's a multiuser system (UNIX, NetWare Connect, etc.)
- you just can't reboot the system every time a modem gets confused.
-
- If none of these requirements apply to you, then an internal is as good as an
- external, and cheaper.
-
- Geoffrey Welsh, Developer, InSystems Technologies Inc.: insystem@pathcom.com
- At home: geoff@zswamp.uucp, [xenitec.on.ca|m2xenix.psg.com]!zswamp!geoff
-