Go Concurrent, Not Sequential, In ESL SoC Design

Complexity is forcing many embedded-system designers to consider virtual platforms for concurrent hardware and software development. The typical sequential process for writing and validating software, which usually happens only after a hardware prototype is available, isn't working. Using virtual platforms at the electronic system level (ESL) in lieu of a hardware prototype offers a much more concurrent and efficient path.

Further, virtual platforms—simulation-based, architectural models of the system—let designers work through the complex tradeoffs in systems with multiple processors and many peripherals. The platform can ensure that a "golden" behavioral specification is fixed early on for comparison later in the cycle.

Such a virtual-platform environment is embodied in VaST Systems Technology's CoMET, METeor, and Metrix products. The CoMET system-level tool builds and refines the virtual hardware platform for the system being designed. Employing processor models supplied by VaST Systems and the designer's bus and peripheral models, CoMET can analyze many candidate system hardware platforms very quickly. CoMET delivers simulation speeds from 20 to 200 MIPS in cycle-accurate mode for processors and up to 2 million transactions/s for buses.

On the software side, METeor is a real-time embedded software-development environment that uses the virtual platforms created in CoMET. Once the hardware team settles on its architecture, the software developers can import the virtual platform representing that architecture into METeor. METeor enables them to run their code as if it were running on a single-board computer that mirrors the reference architecture.

The recent Metrix tool allows designers to put virtual probes into the virtual platform to pull performance data out, filter it, and present it in graphical or text forms. Also, it examines what's going on within complex systems in both hardware and software, quantitatively assessing behavior and performance.

A virtual platform environment, such as the one from VaST Systems, brings enormous potential cost and time savings to the embedded development process (see the figure). Software teams can start shaking out their code on the reference model even as RTL coding work begins on the hardware. The fact that environments such as CoMET can handle mixed-mode simulation makes it all the more efficient.

According to VaST, the cycle-accurate virtual platforms can be refined into RTL, yet today refinement is an iterative manual process. But at least you're starting with a model that has been validated against system software.

CoMET, including Metrix, typically costs $80,000/system. METeor (with Metrix) costs $35,000/system.