You can use CPortLib2 ActiveX controls for communication with various devices through standard serial interface (RS-232). This library includes 2 freeware ActiveX controls - visible CPortLibX2 (RS232 terminal) and invisible CoCPortLib2. Both controls are in fact simple ActiveX wrappers around popular CPortLib VCL components written by Dejan Crnila.
Unlike DMForms ActiveX controls library, CPortLib2.ocx doesn't depend on DM2003 installation and may be used separately. It is distributed under terms and conditions of Mozilla Public License (MPL) and includes full source code (required code of CPortLib VCL may be downloaded from project home page at Source Forge).
Comparing to appropriate controls from DMForms, CPortLibX2 and CoCPortLib2 implement several additional features (see below). Both controls have the same common interfaces.
Installation of CPortLib2 ActiveX control is very simple and doesn't require special installer software. Unpack the contents of the archive into some folder on your hard drive and run COM registration utility from the command prompt as shown below:
Keep in mind that on Windows NT systems installation folder must have correct security settings, and you also must log in with appropriate access rights. Uninstall is also very straightforward - just type in the command prompt:
regsvr32 /u CPortLib2.ocx
and after you will see confirmation message you can delete the whole contents of the installation folder. If you intend to include CPortLib2.ocx unit into your setup, don't forget to mark this file for self-registration, or configure your setup so that it will be correctly registered.