Modem recognition

  • Thread starter Thread starter Owen.C
  • Start date Start date
O

Owen.C

I have an external Intel V92 modem. Windows XP Home does
not recognise this at start up. After each start I must
scan for hardware changes in Device Manager. It finds it
OK and away we go. I have been thru' troubleshooter to no
avail. Any ideas? Thanks.
 
The external modem MUST be turned on before you start Windows XP. Windows
XP "frees" up unused resources (IRQ, DMA, ram etc...) by turning off
hardware it can not find.

Y.
 
That's a cop-out, not a solution.
If that is Microsoft's "logic", why then does it not
refuse to recognise eg: USB printers/cameras unless they
are connected at boot-time?
The serial port (eg: 3F8) and IRQ (3/4) are permanent
features of the actual hardware, so you can't exactly free
them up. XP & 2000 are very "heavy" systems in terms of
the disk space they use: it would not require rocket-
science technology to simply monitor the Modem Status
Register. A change in bit 4 indicates that CTS has gone
high/low. For goodness sake: there's even a built-in
Interrupt register which generates hardware interrupts
when there is a change of status on a serial port!! The
above whinge is only applicable to modems connected in
the "old fashioned" way to a serial port. Ho hum: back to
plug 'n pray......
 
The external modems which use the standard com port do behave the way I
describe. To only way to get them back is to refresh the Device Manager
configuration. This is the same for parallel port devices, other than
printers, and SCSI devices. It seems that Microsoft did not bother in
updating the port device drivers so as to use newer WDM model.

As for USB and Firewire devices, they base port drivers appear to "poll' the
USB/Firewire line periodically to see if any devices are added/removed.

Y.
 
I recently upgraded hardware and installed XP. Then had the same problem as
you.
XP could not find the drivers for my modem and selected what it thought was
best fit, a Rockwell PnP modem.
This would work fine, if like yourself the modem was on at bootup.
I downloaded slightly more up-to-date drivers and installed them.
I then deleted and re-installed the modem, taking the manual option in every
case when Windows asked if I wanted it to install "automatically". Finally
after several attempts I installed the modem & windows accepted it.
It now works at any time, even if it was not on at bootup. The modem is
*not* shown as a PnP modem.
Best of luck,
GR
 
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