The userBlock() function is called at each time step to calculate simulation values. It is the only function a DLL is required to export.
The userBlock() function may be called an arbitrary number of times during a time step interval. The number of calls depends on the integration method and whether the VBF_HAS_STATE flag is active for a block. Note that the outputs are not preserved from call to call. Thus, this function must write to its outputs at each call.
void PASCAL userBlock(double param[], double inSig[], double outSig[])
The inSig array is filled by Embed with the values presented to the input connectors on the userFunction block. Store the result values in the outSig array. Embed presents the outSig values to the corresponding output connectors on the userFunction block.