MAIN RESULTS 157
7.7 SUMMARY
This case provides a good example of how DSM can be used at the lowest end of the
abstraction spectrum, generating assembly language for an 8-bit microprocessor
directly from high-level models. It is interesting to see that even here, the
productivity increase ?¬?ts within the normal range of a factor of 5??“10. At ?¬?rst sight,
there seems little bene?¬?t in replacing a line of code ???Say ???Press?????™ with an object
containing the word ???Press.??? Looking more closely, we notice that in both cases we
need to also specify the starting address and length of the speech sample. If we were
writing the assembly language by hand, we would have to look these up somewhere
and copy them into the code. Here we can simply reuse an existing ???Press???
TextFragment object, and should any of its details change later, those changes will
be automatically re?¬‚ected here. Similarly, rather than having to fathom our way
through the spaghetti of Goto jumps and labels, the models make the control ?¬‚ow
instantly and intuitively clear.
The fact that the modeling language and generators were built in such a short space
of time also provides good evidence for the use of ef?¬?cient DSM tools. It is
particularly important to be able to quickly iterate through several cycles of adding a
small part to the modeling language and testing it, without existing models being
rendered unusable.
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