This user manual describes the NMSIS DSP software library, a suite of common signal processing functions for use on Nuclei N/NX Class Processors based devices.

The library is divided into a number of functions each covering a specific category:

  • Basic math functions

  • Fast math functions

  • Complex math functions

  • Filters

  • Matrix functions

  • Transform functions

  • Motor control functions

  • Statistical functions

  • Support functions

  • Interpolation functions

The library has separate functions for operating on 8-bit integers, 16-bit integers, 32-bit integer and 32-bit floating-point values.

Using the Library

The library functions are declared in the public file riscv_math.h which is placed in the NMSIS/DSP/Include and NMSIS/DSP/PrivateInclude folder.

Simply include this file and link the appropriate library in the application and begin calling the library functions.

The Library supports single public header file riscv_math.h for Nuclei N/NX Class Processors cores with little endian. Same header file will be used for floating point unit(FPU) variants.


The library ships with a number of examples which demonstrate how to use the library functions.

Toolchain Support

The library has been developed and tested with RISCV GCC Toolchain.

The library is being tested in GCC toolchain and updates on this activity will be made available shortly.

Building the Library

The library installer contains a Makefile to rebuild libraries on Nuclei RISCV GCC toolchain in the NMSIS/ folder.

The libraries can be built by run make gen_dsp_lib, it will build and install DSP library into Library/DSP/GCC folder.

Preprocessor Macros

Each library project have different pre-processor macros controlled via CMakeLists.txt.

This library is only built for little endian targets.