Electronic Team, Inc. uses cookies to personalize your experience on our website. By continuing to use this site, you agree to our cookie policy. Click here to learn more.

Null-Modem Emulator: Choose the Best Solution

Olga Weis Olga Weis

A Virtual Null Modem is a program or software solution that can emulate multiple RS232 port pairs that are connected with the help of a null modem cable.

It’s possible to create several virtual serial ports practically similar to actual ports like COM127, COM11, COM10, etc. These are connected by the virtual null modem cable in pairs. A Virtual Null Modem lets you create any number of ports based on the system resources you have.

So, if you need to use a virtual null-modem connection and are looking for a solution to do that, read on. Virtual Serial Port Driver and Null-Modem by Com-0-Com are two great options for this.

Let’s compare them to find which among them is better suitable for your needs.

Try Virtual Serial Port Driver
14-day free trial

Virtual Serial Port Driver by Electronic Team

Electronic Team’s Virtual Serial Port Driver is an advanced virtual null-modem software solution. This commercial, professional-grade tool can easily create multiple virtual COM port pairs connected through a virtual null modem.

Next, these port pairs facilitate a virtual communication bridge to enable data from an application at one end of the pair to get transmitted and immediately received by another application at another end of the pair.

Virtual Serial Port Driver offers a rich set of features to solve issues that are caused by the absence of serial physical interfaces on modern systems. It allows you to test programs via support control signals, high transmission speeds, and virtual ports. As it can create ports immediately, it lets you work with these ports before the PnP manager identifies the new ports.

Some of its key features include:

  • Multiple port creation
  • Easy port management
  • Quick port deletion
  • Fully emulating real/physical port settings
  • Managing signal lines
  • Supports Windows 10

So, if you want to leverage a high-quality virtual null modem emulator, Virtual COM Port Driver can be a great option to meet your needs.

Null-modem emulator by com0com

Com0com’s Null-modem emulator is a kernel-mode, open-source virtual serial port driver. It has a GPL license and is available for free use.

This emulator lets you create unlimited pairs of virtual COM ports. You can use any of these pairs to connect an application (based on a COM port) to another application. Here, each port pair offers two COM ports. One port’s output will be the input from another port, and vice versa.

Furthermore, you can use Null-modem emulator to provide a serial interface for a device emulator and COM port redirectors.

  • For device emulator: In this scenario, the device emulator utilizes one port pair while the DOS or Windows application uses another port. This DOS or Windows application requires a COM port for interacting with the device.

    For instance, if you want to send or receive faxes over your IP, connect the Windows Fax app to t38modem via a virtual pair of the COM port.

  • For COM port redirectors: Using com2tcp, You can interact through a serial interface on a TCP/IP server. If you like using com2tcp but require more features, like support for RFC 2217, hub4com is a good option.

Hub4com is a part of com0com that lets you manage signals and data from a serial device using multiple applications. For example, many apps can easily exchange data from a single GPS device. In addition, hub4com allows using a remote computer’s real/physical serial ports as if these ports are actually present on a local computer.

Virtual Serial Port Driver vs. Null-modem emulator

Let’s compare key features of Null-modem emulator by com0com and Virtual Serial Port Driver by Electronic Team. This will help you make a better decision. The below table has the benefits of using the paid software vs free and open source.

Features list
Virtual Serial Port Driver Electronic Team
Null-modem emulator com0com
Tested version
The proprietary licensing scheme that does not oblige you to expose the complete source code of your own derivative works which are based on or incorporate any part of the program
The out-of-the-box solution that does not require any additional software or drivers
Availability of customer support service assisting in matters related to software usage, installation, and configuration
High-level technical assistance during software customization and integration into your industry-specific products
Regular software updates and improvements
Drivers successfully passed Microsoft Windows Hardware Quality Labs (WHQL) tests and are digitally signed by Microsoft
Any number of virtual serial ports pairs can be created
Full software emulation of real serial port
Hot virtual ports installation - no reboot required after installation, creation or reconfiguration of virtual serial ports
Link between virtual serial ports is much faster than real null-modem cable connection and solely depends on your processor speed
Virtual serial port may have any name you like (not only COMx)
Virtual serial ports are located in Device Manager, thus any software finds the ports
Virtual ports are located in "Ports" group of Device Manager
(all ports)
(only COMx ports)
Possibility to create ports for the current user session only. Allows RDP users to create port with the same name (e.g. COM1) in each user session.
Ports are automatically re-created on system reboot (prior to user login)
Get information about current virtual serial port state, amount of sent/received data
Virtual serial port can have the same name as real serial port (virtual serial port overlapping)
Emulate virtual serial line connection break
Manage port access list, which is used to restrict access to created ports for various applications
Different virtual null-modem schemes are available
Ability to save null-modem scheme as a template
Full support of Flow control (Hardware and Xon/Xoff)
All signal lines supported (DTR/DSR/CTS/RTS/DCD/RI)
Strict baudrate emulation
Make virtual ports available for printers, registering virtual serial ports in Windows Registry so, that they can be selected in Add Printer Wizard
Drivers and binaries are signed by company certificate
Works on Windows 10 with UEFI and Secure Boot enabled
Virtual pair settings can be changed without the need of closing ports
Virtual pair can be deleted without the need of closing ports
Remove all virtual pairs in one click
Instantaneous ports creation lets working with them even before PnP manager detects the newly added ports
Virtual port properties window in device manager has a tab with port information and statistics
All Windows operating systems supported
Windows 7 32
Windows 7 64
Windows 10 32
Windows 10 64
Windows Server 2012 R2
Windows Server 2016
Free version available
no (trial)
No Net Framework required for GUI to run
Requesting Administrator privileges: start / GUI operation
You can enable automatic update of ports’ list, thus you can see pairs created in other user sessions
Possibility to change company in device name shown in Device Manager


Virtual Serial Port Drive (VSPD) is a professional-grade virtual null-modem software that’s efficient and comes with useful features. It not only lets you create numerous virtual COM ports quickly but also provides you with great options to enable full serial port emulation.


Suppose you want to link two given programs. In general, you will need two serial ports that are connected with the help of a null modem cable to do that.

However, most modern computers are built with just a single port. This is the case with desktops, while laptops don't even have any ports.

So, to use the Virtual Null Modem software, you will need to emulate a null modem connection. Doing this will enable two programs to interact with one another on the same computer system. And the best thing is, this won't require any extra software or hardware.
A null modem cable's purpose is to enable two RS-232 DTE devices to perform data exchange without using additional equipment, like DCE.

Here, DTE stands for Data Terminal Equipment which are devices and modems that one can control via the text console of the terminal.

Moreover, DCE is Data Circuit-terminating Equipment, which can be devices or computer systems that DTE devices or systems are connected to.
small logo Virtual Serial Port Driver
#1 at Communication Application
Virtual Serial Port Driver
Create virtual COM port pairs in Windows
5 rank based on 367+ users ( Learn more )
Get a download link for your desktop
Submit your email address to get a link for quick download on your desktop and get started!