Serial Port Monitoring Control - ActiveX Component Library for RS232 Data Monitoring, API for Software Developers
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The library is distributed as a single executable file which is signed by the HHD Software, Ltd. You can use the operating system's provided tools to verify the digital signature to make sure the file is delivered unmodified by any third-party and is free of transmission errors.

The library installer, when launched, asks you to provide the library installation path, or to accept the default. You can also choose whether you need the library samples to be installed or not.

After installation, the following structure appears in destination folder:

  • hhdspmc.dll (64-bit version of ActiveX control DLL)
  • DIFxAPI64.dll (64-bit driver installation framework redistributable component)
  • hhdspmc.dll (32-bit version of ActiveX control DLL)
  • DIFxAPI32.dll (32-bit driver installation framework redistributable component)
  • hhdspmc.chm (this documentation)
  • hhdspmc.inf (Driver installation information file)
  • (32-bit driver catalog file)
  • (64-bit driver catalog file)
  • hhdspmc32.sys (32-bit serial filter driver)
  • hhdspmc64.sys (64-bit serial filter driver)
  • hhdspmc.h (Compiled IDL file)
  • hhdspmc.idl (IDL file with library classes and interfaces)
  • hhdspmc.lib (64-bit import library)
  • hhdspmc.lib (32-bit import library)
  • spmc_redist.exe (SPMC redistributable package)
redist/Merge Module/x64
  • spmc_msm_x64.msm (64-bit Windows Installer Merge Module)
redist/Merge Module/x86
  • spmc_msm_x86.msm (32-bit Windows Installer Merge Module)
Contains all SPMC sample projects and solutions

Several files (dynamic-link libraries, drivers and import libraries) are available as 32-bit and 64-bit. When SPMC is installed on 64-bit machine, both 64-bit and 32-bit libraries are registered, allowing all kind of user code to access the library.

On 32-bit machine, on the other hand, only 32-bit library is registered, and you can only run 32-bit client code.