ESL Modeling: Be Careful What You Wish For


I was talking to a customer last week about his most recent ESL activities and he brought up a question that I’ve heard from many different sources : “How accurate does my ESL model need to be?” The level of timing accuracy, and even function accuracy, needed for effective system level analysis is a very dynamic question, with different answers for different organizations, and even different stages of the design process.

I’ve seen many cases where adopting ESL techniques has been successful and those where it has not worked. One of the significant contributing factors in the failed cases is engineering obsessing about the accuracy of the models they are creating. As organizations look at moving to higher levels of modeling, they naturally come up with a wish list of all the possible things they would like to accomplish with these abstract models. The problem occurs when they then take this wish list and try to satisfy all of it right away in the model requirements.

Moving to a new methodology and trying to answer all the possible questions you might want to answer in one step is a monumental task. Organizations that have been successful in adopting ESL focus their initial system modeling task on the simplest questions that will have a significant impact on key architectural decisions. Then they create ESL/TLM system models to answer those specific initial questions. By taking a small revolutionary step in creating the initial ESL/TLM system, they can then refine this system model in an evolutionary process of increasing complexity and accuracy, ultimately answer ing all of the questions before beginning implementation.

I am eager to hear if you have had the same experience , or not , when creating ESL models. So I’ll propose a few open questions for any of you who have been involved in a successful ESL/TLM modeling effort:

  • What has worked for you?
  • What level of accuracy did you require in your models?
  • What types of issues were you addressing with your effort?
–Jon McDonald, technical marketing engineer, Mentor Graphics