For each ASN.1 production defined in the ASN.1 source file, a C encode function is generated. This function will convert a populated C variable of the given type into an encoded ASN.1 message.

If C++ code generation is specified, a control class is generated for certain types - the so-called "PDU" types. The control class includes a generated EncodeTo function which wraps the C encode function. This function is invoked through the parent class's Encode function to convert a populated msgData attribute variable into an encoded ASN.1 message.