Already today more than 90% of all programmable processors are employed
in embedded systems. This number is actually not surprising,
contemplating that in a typical home you might find one or two PCs
equipped with high- of embedded systems, performance standard
processors, but probably dozens including electronic entertainment,
household, and telecom devices, each of them equipped with one or more
embedded processors. Moreover, the elec- tronic components of
upper-class cars incorporate easily over one hundred pro- cessors.
Hence, efficient embedded processor design is certainly an area worth
looking at. The question arises why programmable processors are so
popular in embed- ded system design. The answer lies in the fact that
they help to narrow the gap between chip capacity and designer
productivity. Embedded processors cores are nothing but one step further
towards improved design reuse, just along the lines of standard cells in
logic synthesis and macrocells in RTL synthesis in earlier times of IC
design. Additionally, programmable processors permit to migrate
functionality from hardware to software, resulting in an even improved
reuse factor as well as greatly increased flexibility.