A DSP Coprocessor for ADSL Lite

This paper presents Massana's DSP co-processor solution – FILU-DMT [1] for enabling soft G.Lite (or ADSL Lite) on Pentium and RISC processors. The user interacts with the coprocessor via a C API which accesses a shared RAM interface. All of the G.Lite DSP functions are pre-programmed and held in ROM. The FILU-DMT is implemented in fully synthesizable Verilog RTL with a single synchronous clock for high scan coverage. It is based on a dual MAC architecture which can perform a radix-4 FFT butterfly in 8 cycles yielding a 256 point FFT in 21 µs. This is the industry's fastest FFT for this class of processor. The FILU-DMT supports block floating-point arithmetic which achieves near floating-point performance at a fraction of the area cost of conventional DSPs.