Hi Rick,
Sorry about the delay in the reply.  You wrote to me:
RC>rc> to have jumpers to select the RC>comm port and IRQ, even if they
RC>rc> also support "plug and play".
I take it that "Plug and Play" is an extra added feature to the new
modems and not a prime concern to get them to work on any machine not
having the required bus and board slots on the mother board?
RC>You don't have to configure the external modem at all
Am I using the wrong words here?  May be I should have said initialize?
When you configure your communication software such as Telix, you
have a lot of choices such as setting the baud rate and modem.  Are you
not configuring your modem thru this process whether it is an external
or internal?  Are you also configuring your computer's ports?.
- you just have
RC>to make sure the computer has a comm port properly configured, and
RC>you plug into that.  Most PCs support two comm ports, Com1 and Com2.
RC>If you presently have an internal modem on Com2, when you remove it
RC>you will have to enable the Com2 port in the PC (it would have to be
RC>disabled to allow the internal modem to work on Com2).  So, with an
RC>external modem you have to configure the port, not the modem.
In other words you are changing it back to a Serial Port to I/O
with the external?  This change is not done thru the communication
software right?  It is done thru the operating system.  Explain briefly
please?
RC>If you're running a recent version of DOS, try typing MSD at the DOS
RC>prompt.  That will run the MS Diagnostics.  Select Comm Ports from
RC>the menu and the available ports will be displayed.  Note MSD will
RC>treat your internal modem as a comm port.
OK! I can see that.  What are the key things of importance from this
display.  I can see the UART chip type is significant.  This has to do
with its speed right?  What about the address and other items listed?
What should I be concerned about as to configurations and getting the
modem to work?
RC>ro> came with three jumper banks, two for comm port
selection and the RC>ro> other for irq. It had a sheet of paper with it
that told what RC>ro> each of the jumper combinations in pairs did - ie.
COM1 RC>ro> J17-J13, J15-J16 - IRQ4 J4-J9
I can use this to see that I have the modem set up on the right port
also!.
RC>That's still common.  Most plug-and-play internal modems can be
RC>manually configured using jumpers, and usually that will work better
RC>than relying on Windows to properly configure the modem.  If you buy
RC>a plug-and-play internal, make _sure_ you can manually configure it
RC>if necessary.
RC>ro> Even if I do configure the internal by jumpers I still run the
RC>ro> risk that the Windows SW won't reconfigure its files to the new
RC>ro> modem right?
RC>The problem was most likely the need to _disable_ the PC com port to
RC>permit Windows to "see" the modem.  You can't have two devices (the
RC>internal modem _and_ the com port) sharing the same address and IRQ -
RC>not and expect Windows to work properly, that is. :-)
When you are using the Win 3.1 program, do you have to disable the PC
com port so the modem can be seen before you load the Win 3.1 program?
RC>Win 3.1 and WFWG had no "special" files to handle modems.  Win95 does
RC>- it has a "modem.inf" file, but all that really does is ensure the
RC>modem has the proper init string and is operated at the proper port
RC>speed.  A new modem should come with a Win95 .INF file if the
RC>"standard" .INF files distributed with Win95 are not suitable.
RC>If you have an internal 2400 bps modem running on your system now,
RC>you should be able to replace it with a new internal modem simply by
RC>changing the jumpers on the new modem to match the configuration of
RC>the old.  If you are using Win 3.1 or WFWG, that's all you have to
RC>do.  If you're running Win95, after plugging the modem in you simply
RC>have to run the Install program, and, if your modem is properly
RC>configured (the jumpers) it will install and work without a problem.
Ok thats a relief!
RC>Chances are you won't see an 8250 (they're old), but the 16550 is a
RC>standard part, and they are a direct replacement for an 8250 or a
RC>16450.  No special card required.
I looked at my current 2400 baud modem via the "msd" command.  It has
the 8250 chip.  Would it do any good to replace it with the direct
replacement?  What would be the advantage?
Does the way you have your Computer's Operating System configured
directly affect the speed of the transfer of data from files being up
loaded or down loaded by the system as a whole?  IE disk access time, or
memory available etc.
RC>ro> While we are talking about speed, I see that there is a lot of
RC>ro> traffic on the board about setting the speed of their modem. I
RC>The modem is generally configured to connect at its fastest speed,
RC>and it negotiates the speed with the remote modem.  That's almost
RC>completely out of your control, and not your concern.  You simply
RC>make sure your port speed is set _higher_ than the modem's maximum
RC>speed:  either 57,600 or 115,200 bps for a 28,800 bps modem.
Please explain the difference between "Port Speed" and "Modem transmit
speed"?  How are they set?  Is the Port Speed what you set in the
Communication program such as Telix?  Is this the maximum rate the
computer will handle bytes coming off or going to the serial board or
internal modem?
New modems compress and decompress the data on
RC>ro> the fly to obtain faster rates of data thru put? When did they
RC>ro> start all this and at what modem speed did compression take
RC>ro> place?
If you buy a used modem today, what vintage would you look for to expect
to see all these new improvements.  Ie compression and error correction?
Is both the compression and the error correction done thru the "Chip
Set" on the modem? or do you have to run special accompaning software on
the computer to get these features to work?
RC>My telephone lines allow me connections consistently at 33,600 bps,
RC>but your mileage may vary. :-)  The newer modems have both error
RC>correction and data compression, and both of these _add_ to the
RC>connect speed. The modem _does_ communicate at 33,600 bps, but your
RC>throughput can be higher than that because of error correction and
RC>data compression.  _That's_ why you use a port speed higher than the
RC>modem speed.
If you have not already explained the port speed you mention here please
do so now.  Also does the vintage of the processor in any way effect
port speed?  Since the highest modem bps that I have seen is 57 K bps,
does that mean that a 8 MH processor should be able to handle the thru
put with no problem?  Or is it a function of the type of software
"OVER HEAD / DEGRADATION" you are running that will drastically reduce
you systems capability to thru put at that rate.  Am I forced to go to a
higher speed processor and GUI (graphical user interface) to be able to
use the newer modems and be able to access the internet or an on line
service?
>>> Continued to next message
 * OLX 2.1 TD * I'M DOING BETTER, I'VE ONLY JUMPED THE RAILS ONCE TODAY!
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