SnappyWinscard is a .NET interface for smart card readers like ACS ACR122U.
Now also supports 64bit. Currently in beta state.
Initial NuGet package, 32bit only.
You can get the NuGet package here.
The project CardTest contains a desktop application that can show and test the capabilities of SnappyWinscard. Using this you can read and write data from and to your smartcard.