CPUs

The Central Processing Unit (CPU) is the most important part of a computer. This is where all the instructions are sent and handled. Here we compare the average Palm CPU against a Pentium III.

The Palm CPU

The most common processor used in Palms is the Dragonball EZ (DBEZ). The DBEZ is driven by the 68EC000 CPU manufactured by Motorola. This chip was initially introduced in the 1980s and was the CPU of the original Macintosh and Amiga. It was also later used in the Sega Saturn.

68EC000 Specifications:

· Complex Instruction Set Computer (CISC)
· 56 types of instructions
· 5 data types
· 14 addressing modes
· 16 32-bit registers split into data and address registers. One address register is reserved for the Stack Pointer.
· 2 stage pipeline. It can fetch the next instruction during execution.
· 68,000 transistors

The 68EC000 does not have floating point hardware (although it supports floating point operations), onboard cache or memory management.

The Pentium III CPU

This is the PC many of us owned in the year 2000. When it was released it was the world's highest performance microprocessor for PCs.

Pentium III Specifications:

· Reduced Instruction Set Computer (RISC) with a CISC-RISC Translator
· 70 new instructions
· 500 MHz clock rate
· External bus runs at 100 or 133 MHz
· 16 KB first-level cache
· 512 KB of off-chip secondary cache
· Combined 20+ million transistors in the caches.
· 3-way superscalar execution.
· 14 stage pipeline.
· Supports multiple branch prediction, data flow analysis and speculative execution.
· Has Dual Independent Bus Architecture, Advanced Transfer Cache and Advanced System Buffering
· Has Internet Streaming Single Instruction Stream - Multiple Data Stream (SIMD) Extensions.

Conclusion

Its all about having the right tools for the job. A Pentium III is clearly a much more powerful machine than the Dragonball EZ's processor, but you don't need blazing floating point performance for what is basically an electronic scheduler.