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ptran2000

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com port redirection?

I heard that MSDOS apps can use a pci modem running under Windows 2000 OS, with the help of redirection.  Is this the same as issuing net use command.  Can someone tell me how to do this.

thanks
Ptran2000
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kawboy20

ptran2000,

You can try the product ViP http://store.yahoo.com/pcw2/turvipdow.html

A DOS communications program is written with the assumption that the software will be interacting with a UART, which for legacy modems was not an issue, but PCI-bus modems and USB-based modems crate a virual port that the DOS app can not communicate. Supposily ViP acts as midleware to allow windows DOS apps to talk to software modems. If the app is running in native DOS I don't think it is possible.
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This product is only for win 9.x.  I have this on a win98 computer already and it works fine on win98.
Ptran2000,

The net use command can only be used in the following ways:
net use <drive letter>\\unc path
net use lptx:\\unc path

I'm assuming the DOS app is configured to use a certain port like com 2. You might try using an external modem attached to a serial port 2 which by default is com 2, but I don't think it's possible to redirect a com port to the vitual port for the PCI modem. Hope that helps
unfortunately external modems and ISA modems are not an option.
It's not going to work. This app expects to be able to talk to the hardware directly. Win2K will not allow this. Period. No redirection is going to let this happen; the architecture won't allow it.


"Under Windows XP, NT and 2000, DOS applications that manipulate the UART hardware directly are able to access both DialOut and standard ports in the COM 1-4 range using the NTVDM driver (NT Virtual DOS Machine) that ships with these versions of Windows. The NTVDM is a library that maps 16-bit APIs into 32-bit APIs. It is installed by default. "

url: http://www.pcmicro.com/serialip/guide/ch3-dossupport.html

doesn't this state that it is possible??????

thanks
ptran2000
I think you missed the second paragraph which gives a more full picture:

DOS applications will not be able to access ports COM5 and above using this mechanism, however. Also be aware that Tactical Software's testing has shown that not all DOS applications perform well under NTVDM, even with the standard COM port driver.

This is a situation where, if it is going to work it is going to work and if it isn't, it isn't. There are no hacks or workarounds. Part of NT/Win2K/XP's design is to prevent rogue apps from directly accessing the hardware; they have to go through a system API, no ifs, ands or buts. Apparently _some_ serial apps written for WinMe and lower _might_ work, but there are no guarantees. And if they don't work through the NTVDM in this manner, they are SOL.

Advice: use an upgraded app or downgrade the OS.
I got it to work with WinXP! Using a Zoom and USR PCI controller based modem.  
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