Serial Port Mapper allows you to map any serial ports to any other serial ports. For example you install additional serial port expansion card to computer as COM7 serial port but your favorite software can work with COM1...COM4 ports only. To resolve this problem you can use Serial Port Mapper to map new COM7 port either to COM1 or to COM2...COM4. Now your software can open COM1 port (or COM2...COM4) but actually work with new COM7 port.

SRedirect is a command line utility that allows a remote TCP/IP connection to a serial port. SRedirect redirects all RS-232 data from a TCP/IP port to and from the local serial port. SRedirect creates a server for ONE local serial communications (COM) port. SRedirect allows connection of a client application. SRedirect transfers data in both directions between the connected client and the local COM port.

Free Port Scanner is a small, fast, easy-to-use and robust port scanner for the Win32 platform.You can scan ports on fast machines in a few seconds and can perform scan on predefined port ranges. This tool uses TCP packets to determine available hosts and open ports, service associated with port and other important characteristics. The tool is designed with a user-friendly interface and is easy to use.

Software serial port monitor Rs232 sniffer with protocol analyzer and packet data logger. This monitoring utility can spy, capture, view, log, analyze, test com ports activity performing com port connection and traffic analysis with data acquisition and control. You can use this system as device interface testing tool, modem data transfer viewer and so on.

Eltima Serial Port Terminal is an ideal tool for testing, debugging and troubleshooting serial port devices. It lets you work with numerous number of ports simultaneously, both serial and virtual ones. You can easily alter baudrate, databits, parity, stop bits, flow control parameters and dynamically apply these changes to serial port settings on the go. You can always check for history of typed commands.

PortMarshaller is a software-based TCP/IP port forwarder. The software accepts connections on a particular TCP port, and establishes connections to a different TCP port to fulfill requests.

COM Port Toolkit is an integrated serial communications testing toolkit. It sends user's data to and receives one from a device and records all transfers to a log.

You can test equipments serial communications protocol by hand: feed it input, check the output.

COM Port Toolkit can capture serial communications between the device and the software by using special serial port driver.

Create and manage virtual serial ports from .NET and Visual Basic (ActiveX)
Using Virtual Serial Port SDK you can create a "new" serial port on your computer. This serial port is completely controlled by your application. Other 3rd party applications can connect to this serial port and believe it is a normal serial port.
Windows Mobile/Pocket PC, Windows XP/2k/NT and Windows ME/98.
Samples in C#, VB.NET and VB6

1st Ip Port Scanner is a very useful Ip Scanner and Port Scanner. It builds ip finder port finder ip scanner port scanner and ip tracer ip tracker ip camera in one software. It can find ip address,search ip address,trace ip address and scan ip address.And it also can find port,search port and scan port.It is easy and fast!
1st Ip Port Scanner allows for testing whether a remote computer is alive with three types ICMP, SYN and UDP.

Serial Port ActiveX Control is a powerful component that lets developers quickly and effectively work with serial port. Use Serial Port component to easily communicate with external devices on RS232 connection, such as modems, bar code readers, PBX and so on. Serial Port introduces several extremely useful properties for detailed setting of serial port, numerous methods to write and read from port and events to control serial port state changes.

Free software serial port monitor, Com Rs232 sniffer with communication packet data analyzer. This monitoring utility can spy, capture, view, analyze, test com ports activity performing com port connection and traffic analysis with data acquisition and control. You can use this system as device interface testing tool, modem data transfer viewer and so on.