Win4Lin User's Guide

About COM Port Device Definition

DOS and Windows sessions can use COM ports by having Linux control the physical port (virtual attachment).

Direct attachment is less reliable when the system is heavily loaded, but it may be faster than virtual attachment.

Use this view of the Device Definition window to view or modify existing COM1 and COM2 port definitions. Depending on which type of COM token you have selected, the information displayed will either contain a virtual or a direct attach device definition.

Using this view, you can also delete existing COM port definitions or create new ones.

For more information about the general subject of device definitions and managing them, see About Device Definition.

COM Port Direct Attach Device Definition

A COM port direct attach device is a serial port that a DOS or Windows session controls directly, without interfacing with Linux or Win4Lin.

COM port devices defined here are available for attachment in the COM1 or COM2 selection lists in the Devices view of the Personal Win4Lin Session Configuration window.

IRQ and IO Port Specification

COM ports use a single IRQ and a simple IO port range, which you specify in the IRQ and IO Port text boxes.

For COM1 direct attach device definitions:

For COM2 definitions:

You may also specify nonstandard COM port direct attach devices, but their use may not be compatible with Win4Lin.

Creating New Definitions

Take the following steps when you create a new COM port direct attach device definition:

  1. Click on the New button to create a new token name for the COM port device. Alternatively, you can select an existing definition (e.g., dcom1) from the list of tokens, modify the settings appropriately, and then save the resulting definition under a new token name.

  2. Click on the Add button below the IRQ list box, and enter the IRQ the device uses.

    If you make a mistake, click on the incorrect entry to highlight it, and then click on the Remove button below the IRQ list box to delete the incorrect entry. Then, reenter the correct IRQ as described in step 2.

  3. Click on the Add button below the IO Port list box, and enter the IO port address range that the device uses.

    If you make a mistake, click on the incorrect entry to highlight it, and then click on the Remove button below the IO Port list box to delete the incorrect entry. Then, reenter the correct address range as described in step 3.

  4. Enter a description for the device in the Description text box, and specify the appropriate Usable By and Failure Action settings. See About Device Definition if you need an explanation of the appropriate settings for these fields.

  5. Click on the Save or Save As button to save your new COM port definition. You can now use the Devices view of the Personal Win4Lin Session Configuration window to attach this device to a DOS or Windows session.