The Specification and Description Language (SDL-2000) has formal definitions for syntax, well-formedness, and dynamic semantics. While these definitions have well-understood mathematical foundations, engineers prefer to execute formal definitions, instead of studying them on paper.We present a tool chain which starts with the formal definition, and translates that into a compiler. The resulting compiler starts with a textual representation of the specification, and produces a program in the underlying formal calculus (Abstract State Machines, ASM). The ASM program, when executed, produces a trace of the SDL specification according to the formal language definition. In the process of developing this compiler, a number of errors were found in the formal semantics, which have been corrected.