RISC-V Based Processor Architecture for an Embedded Visible Light Spectrophotometer

The miniaturization of sensing systems often requires embedding an electronic subsystem for local or edge computing, or to interface with the sensor for pre-processing operations. The sensing part of the work presented in this paper is an optoelectronic system that measures neurotransmitters concentration based on visible spectroscopy and that is currently implemented with an external processor in a computer. This paper presents a System on a Chip (SoC) design based on the RISC-V processor and the required peripheral interfaces to replace the current system. The new design is first simulated and then implemented on Cyclone IV and Xilinx ZCU102 FPGAs to explore the usability and advantages of the approach. Both architectures were similar in terms of memory and register use, but the ZCU102-based system used 18016 logic elements, while the Cyclone IV-based one used much less, 13468 logic elements. We also observed a significant difference in frequency of operation, with Cyclone IV was running at 27.84 MHz and ZCU102 at 125 MHz clock speeds.