This paper presents the architecture of a newly-developed dual-issue RISC processor, D10V, that achieves both high throughput signal processing capability and maintains flexibility for general purpose applications. The RISC processor uses a 2-way VLIW architecture with a 32-bit wide instruction word. Two sub-instructions in a VLIW instruction are executed in two execution units in parallel. It also has several enhancements for signal processing. The processor includes pipelined multiply-and-accumulate instructions allowing a new multiply operation to be initiated every clock cycle and block repeat instructions for zero delay penalty loops. Single-cycle data moves of double-word data elements with modulo addressing are provided to deliver required memory bandwidth for signal processing applications. As a result, the D10V achieves high signal processing capability as 1 clock cycle per tap for FIR filtering. Also, several DSP benchmarks illustrate that the D10V competes favorably and in some instances outperforms conventional 16-bit DSPs. For master controlling application, the processor provides memory operations for signed/unsigned byte and bit wise operations. It shows 49 Dhrystone MIPS at 52 MHz, for general purpose applications.

A high-speed 32-bit RISC microcontroller has been developed. In order to realize high-speed operation with minimum hardware resource, we have developed new design and analysis methods such as a clock distribution, a bus-line layout, and an IR drop analysis. As a result, high-speed operation of 400 MHz has been achieved with power dissipation of 0.96 W at 1.8 V.

This paper details a unique VLSI design scheme which employs self-timed circuits. A 32-bit 50-MFLOPS data-driven microprocessor has been designed using a self-timed clocking scheme. This high performance data-driven microprocessor with sophisticated functions has been designed by a combination of several kinds of self-timed components. All functional blocks in the microprocessor are driven by self-timed clocks. The microprocessor integrates 700,000 devices in a 14.65 mm14.65 mm die area using double polysilicon double metal 0.8 µm CMOS technology.

A low-power microcontroller has been developed with 0.10 µm bulk compatible body-tied SOI technology. For this work, only two new masks are required. For the other layers, existing masks of a prior work developed with 0.18 µm bulk CMOS technology can be applied without any changes. With the SOI technology, the high-speed operation of over 600 MHz has been achieved at a supply voltage of 1.2 V, which is 1.5 times faster than prior work. Also, a five times improvement in the power-delay product has been achieved at a supply voltage 0.8 V. Moreover, the compatibility of the SOI technology with bulk CMOS has been verified, because all circuit blocks of the chip, including logic, memory, analog circuit, and PLL, are completely functional, even though only two new masks are used.