picoJave Microprocessor Core Overview

picoJava Microprocessor Cores are uniquely designed processor cores that natively execute Java bytecode as defined by the Java Virtual Machine (JVM). They can also execute legacy C/C++ code as efficiently as comparable RISC CPU architectures. This approach results in the fastest Java runtime performance with a small memory footprint and competitive performance on code not written in the Java language.

Alternatives for executing Java code

As illustrated in Figure 1, there are three alternatives for executing Java code:

• Through an interpreter, which considerably slows execution (see Figure 1-A).
• With a JIT (Just In Time) compiler that can speed execution but expands the code size by a factor of three or more (see figure 1-B). This memory size penalty is a big problem for embedded applications with their restricted memory requirements. Non-native Java-emulating embedded microprocessors use this approach.
• Using direct execution of the Java bytecode, which accelerates the JVM runtime environment with a very small footprint (see Figure 1-C). The picoJava core I and II achieve efficiency in speed and memory for embedded applications by natively executing the Java bytecode directly in hardware.

High-Performance Architecture

Leveraging on the RISC expertise - including methodology, process and circuit techniques - developed by Sun Microsystems over the past 15 years with its high-performance workstation and SPARC architectures, the picoJava cores are streamlined for maximum Java runtime performance. Great care was taken to make the core easy to customize for Java-centric applications by allowing variable-sized caches and versions with or without a floating-point unit along side a standard integer unit as illustrated in Figure 2.

Licensable Cores

picoJava I and II are licensable cores, which can be integrated with the application specific I/O functions to design a complete embedded processor that is ideally suited for Internet Information Appliances such as:

• Digital set-top boxes
• Internet TVs
• Internet screen phones
• Automotive communications devices

Contact Information

• Licensing opportunities: Hugh Cree, (858) 622-2942
• Technical inquiries: Vivek Sardana, (408) 544-0107