Chip rewires itself on the fly
A start-up called Stretch says that its new software-configurable design allows processors to add instructions while they're operating.
The Mountain View, Calif.-based company on Monday announced the S5000, which it says is the first processor that can add new instructions while operating. The chip combines an existing RISC (reduced instruction set computing) architecture with a large reconfigurable area of programmable logic called the Instruction Set Extension Fabric, ISEF. The company's own C/C++ compiler automatically spots areas in a program that require intensive computation and creates new instructions for the processor to handle those tasks.
"Operations that might have needed hundreds or thousands of standard instructions can be handled in one," said Gary Banta, chief executive of Stretch. "Designers that have had to use multiple digital signal processor chips or a dedicated programmable logic chip coupled to a general-purpose processor can get equivalent performance with the S5000, just through writing high-level software."
Typical tasks, such as performing encryption or digital video processing on blocks of data, can be executed in single clock cycles.
Banta said the chip has demonstrated 300MHz performance, outperforming 2GHz competition.
In designs in which the chip replaces a full custom circuit, development costs can be reduced from millions of dollars to tens of thousands, while development time can be reduced from over a year to a few weeks, Banta said.
"It takes far less time and money to develop products using the S5000, and major changes to functionality can be implemented with software updates," he said.
Inside the chip, the ISEF is coupled to the rest of the circuit by 128-bit buses and has 32 128-bit registers. It runs in parallel with other areas of the processor, effectively becoming a fully reconfigurable co-processor, and can be reprogrammed for new instructions at any time during operation.
Stretch provides a development environment that runs under Microsoft XP or Linux and run-time support through its own BIOS (basic input/output system) and for MontaVista Linux, which is a popular distribution for embedded developers.
Intended initially for video, networking, communications, medical and security applications, the processor will become available in a number of configurations during 2004 and will cost between $35 and $100 in production quantities.
Rupert Goodwins of ZDNet UK reported from London.