Asynchronous serial communications made easy for your Delphi & C++Builder applications. TMS Async is a communications package containing components which provide access to the serial ports under Windows. The event-driven architecture provides the highest possible performance and allows all the tools to run in the background.

ZylSerialPort.NET is a thread based, event driven, asynchronous serial port .NET component. Use ZylSerialPort.NET component to easily communicate with external devices on serial port connection, such as modems, bar code readers, GSM modules and others.

Delphi component for serial communication for OS X.

Features:

Communication with devices connected to serial port
Available for Delphi XE3 - XE7
Source code included in full version
Royalty free distribution in applications

Virtual Serial Port Driver creates virtual serial ports and connects them in pairs via virtual null modem cable. Applications on both ends of the pair will be able to exchange data in such a way, that everything written to the first port will appear in the second one and backwards.

Docklight is a testing, analysis and simulation tool for serial communication protocols (RS232, RS485/422 and others). It allows you to monitor the communication between two serial devices or to test the serial communication of a single device. Docklight significantly increases productivity in a broad range of industries, including automation and control, communications, automotive, equipment manufacturers, and embedded / consumer products. Docklight is easy to use and runs on almost any standard PC using Windows 8, Windows 7, Windows Vista or Windows XP operating system.

Simulating serial protocols
Logging RS232 data
Detecting specific data sequences
Responding to incoming data

VMProtect protects code by executing it on a virtual machine with non-standard architecture that makes it extremely difficult to analyze and crack the software. Besides that, VMProtect generates and verifies serial numbers, limits free upgrades and much more.

Serial communication component for .NET.

communication with any device connected to serial port
easy of use and very powerful
uses multithreading and overlapping for maximum performance
available for .NET 2 - 4
source code included in full version
royalty free distribution in applications

ZylGPSReceiver is an award-winning Delphi & C++Builder component collection that communicates with a GPS receiver (Global Positioning System).
It returns latitude, longitude, altitude, speed, heading and many other useful parameters of the current position and the parameters of the satellites in view. The component is extended to calculate distances and make conversions between different measurement units. This component works with any NMEA 0183 compilant GPS receiver connected to one of the serial ports. NMEA 0183 (or NMEA for short) is a combined electrical and data specification for communication between marine electronic devices such as echo sounder, sonars, Anemometer (winds speed and direction), gyrocompass, autopilot, GPS receivers and many other types of instruments. It has been defined by, and is controlled by, the US-based National Marine Electronics Association. You can use it also with USB, IrDA and Bluetooth devices, because these devices have a driver that redirects the input from the USB, IrDA or Bluetooth port to a virtual serial port (you can check it in System/Device Manager/Ports). If your USB device is not provided with such a driver, then use a USB controller whose vendor provides a virtual serial port driver, such as FTDI or use a USB/RS-232 adapter. For Garmin receivers you have to install Spanner software.