Embedded systems are hard to program. Much of the effort is concentrat
ed on processor-management code, effort totally unrelated to the appli
cation being built. Concurrent programming in embedded systems introdu
ces even more problems - mechanisms are needed to protect critical dat
a areas. The application of object modeling to such mechanisms results
in numerous benefits: fewer programming errors, enhanced portability
and improved reuse. We present some simple techniques for realising th
ese benefits.