Changing cores

MIPS Technologies’ Pro Series family of processor cores allows users to optimise their processors for specific applications while maintaining compatibility with the MIPS industry standard architecture.

This new capability is offered through what the company calls the ‘CorExtend’ feature of its Pro Series cores that lets designers define and add their own instructions that operate on data in the general-purpose registers in the same manner as standard MIPS instructions.

To demonstrate how designers can take advantage of CorExtend instructions in their applications, MIPS Technologies has developed several reference designs for multimedia, Voice over Packet, and DSP filtering applications. Application notes and other documentation on the reference designs may be downloaded from the company web site.

‘The DSP filter reference design is an excellent example of the CorExtend capabilities. In only a few weeks, using standard tools and software, an application engineer analysed FIR, LMS, and complex FIR filter algorithms and simulated a prototype core employing several assembly CorExtend instructions. The instructions accelerated these filters (over the optimised assembly code) by about 300% and required less than 25K gates to implement. In many systems this will mean that a fixed-function, hardwired logic block or a hard-to-use special-purpose coprocessor can be eliminated. The resulting SOC will cost less and-perhaps even more importantly-be more flexible and programmable,’ said Victor Peng, vice president of engineering at MIPS Technologies.

Designers can implement their CorExtend instructions in RTL using standard Verilog tools. With the approach, there is no need to learn a new proprietary development language, and the intellectual property embodied in CorExtend instructions remains in the hands of the developer at all times.

Development tool support for the Pro Series family includes the MULTI IDE and optimising compilers from Green Hills Software and MIPS Technologies’ MIPSsim simulator that can be obtained either from Green Hills Software or MIPS Technologies. The MIPS SDE 5.0 software development environment release fully supports the CorExtend features of the Pro Series family.

The Pro Series family currently includes the 4KE Pro family, and the M4K and 4KSd Pro cores. More Pro Series family cores will be forthcoming.