Hello, I've been following the example in App Note 154 which describes how to build virtual peripherals. However, when I select the A/D converter under the Peripherals menu, I get the following popup error: Debug Assertion Failed! Program E:\keil\UV2\Uv2.exe File: afxwin1.inl Line: 22 Abort Retry Ignore I'm on Windows NT 4.0. The dll was built to dynamically link against MFC, since I don't have nafxcwd.lib for a static build. In the source code for the dll, there is a message about having to use the AFX_MANAGE_STATE macro for exported routines that call MFC if the dll is dynamically linked. I'm not familiar with MFC and can't identify them. Could this be the problem? Thanks, Chuck Carlson chuck@sanna.com