onchipuis / mriscv

A 32-bit Microcontroller featuring a RISC-V core

mriscv

Building a pure RV32I Toolchain

The default settings in the riscv-tools build scripts will build a compiler, assembler and linker that can target any RISC-V ISA, but the libraries are built for RV32G and RV64G targets. Follow the instructions below to build a complete toolchain (including libraries) that target a pure RV32I CPU.

The following commands will build the RISC-V gnu toolchain and libraries for a pure RV32I target, and install it in /opt/riscv32i:

# Ubuntu packages needed:
sudo apt-get install autoconf automake autotools-dev curl libmpc-dev libmpfr-dev \
        libgmp-dev gawk build-essential bison flex texinfo gperf libtool patchutils bc

sudo mkdir /opt/riscv32i
sudo chown $USER /opt/riscv32i

git clone https://github.com/riscv/riscv-gnu-toolchain riscv-gnu-toolchain-rv32i
cd riscv-gnu-toolchain-rv32i
git checkout 7e48594
git submodule update --init --recursive

mkdir build; cd build
../configure --with-arch=RV32I --prefix=/opt/riscv32i
make -j$(nproc)

The Microcontroller

The microcontroller is composed by a 32b RISC-V core, a 4KB SRAM, a 10b ADC, a 12b DAC, 8 GPIO, and two SPI interfaces (master and slave). All the modules are conneted using two differente buses: AXI4 and APB.

The directory tree is:

mriscv/mriscv_axi/ADC_interface_AXI -----> ADC interface with the AXI4 bus

mriscv/mriscv_axi/AXI_SP32B1024 -----> SRAM memory interface

mriscv/mriscv_axi/DAC_interface_AXI -----> DAC interface with the AXI4 bus

mriscv/mriscv_axi/axi4_interconnect -----> the AXI4 bus

mriscv/mriscv_axi/impl_axi -----> the microcontroller

mriscv/mriscv_axi/spi_axi_master -----> master SPI used for programming

mriscv/mriscv_axi/spi_axi_slave -----> slave SPI used for data adquisition

Development Board

Also, there are a PCB design for the development board, including circuits for sensing analog signals and the capability to use external clocks. The design is in mriscv/board

mriscv's Issues

Integrating

SP32B1024 module not defined and is being shorted on top module

What is the purpose of this SP32B1024 module? and is it defined anywhere? cannot find it.

Also, Why is the above module AXI_SP32B1024 and SP32B1024 being shorted out.