There are two versions of the `ecgsyn.exe` executable in this directory. Using the ECGSYN source files, the first version was compiled with `Cygwin64 2.6.0 gcc 5.4.0`, and the second version with `MinGW-w64 gcc 4.9.2`, both under Windows 10.

To run the Cygwin executable, you will need to have the Cygwin DLLs installed in your PATH in order to run this program successfully. The simplest and most reliable way to do this is to install the Cygwin development toolkit. To run the MinGW executable, you should install MinGW-w64.