Java is a software developed by Sun Microsystems that, at least theoretically, allows programs to run on a variety of computers without being rewritten for each type. Sun promotes its use in everything from large servers to small devices, such as handheld computers, cell phones and factory-floor robots.
But such devices' constraints, related to cost and processing power, have limited Java's appeal. England's ARM hopes to address those issues with its new chip-design addition called Jazelle, which the company said will increase the speed of Java programs by a factor of eight over current software-based methods, ARM Java program manager Andrew Cummins said Wednesday.
Typically, Java programs run in special software called a "virtual machine" that translates the Java program into instructions a particular chip can understand. But while the virtual machine thus allows Java programs to run unmodified on a number of different computer types, it also increases the processing power demands.
Palo Alto, Calif.-based Sun once had aspirations to make its own Java chips but canceled the plan and decided instead to let other companies license its designs.
The goal of Jazelle is to enable the Java language to run on smaller devices, Cummins said in a presentation at the Microprocessor Forum taking place here this week. "We believe this will make pervasive low-cost Java applications a reality."
In Jazelle, simple Java code is executed through additions to the ARM instruction set. More complex operations, however, are processed in software.
The Jazelle instruction increases the power consumption of an ARM core by only about 10 percent with about 12,000 gates of additional circuitry needed, Cummins said.
ARM designs chips but doesn't sell them. Instead, the company licenses its core to semiconductor makers that incorporate it into chips for cell phones and information appliances. Several companies, such as Intel and Cirrus Logic, license ARM's designs.
Cummins said ARM is initially offering the Jazelle instructions in its ARM 9 family but will add the instructions to its ARM 7 and ARM 10 families next year.