# VSD - RISCV : Instruction Set Architecture (ISA) - Part 1b

### Overview

This course is in continuation with my previous course "VSD - RISCV : Instruction Set Architecture (ISA) - Part 1a" which dealt with RV64I integer instructions. We also looked at a sample program coded in RISC-V assembly language and viewed the contents of all 32 registers present in RISC-V architecture.

All concepts viewed in Part 1a form the basis of this course and viewer is expected to cover Part 1a course atleast 70%. This course deals with some advanced topics of multiply extension (RV64M) and floating point extension (RV64FD) of the RISC-V architecture - An important one needed in today's fast changing computing world.

• Understand RISC-V architecture in greater detail, and, as per speculations and other articles, this is the architecture which you will find in almost 1 trillion mobile devices, this course will make you look at new future
• Learn how computers and processors does basic calculations

### Objective

• Introduction
• Overflow conditions for signed addition and subtraction

• Signed addition and overflow condition for 4-bit word
• Derived overflow conditions for signed addition
• RISC-V overflow checking program for signed addition
• Signed subtraction using addition hardware for 4-bit word
• Overflow condition and conclusion for signed subtraction
• RV64M - Multiply extension instruction set

• Multiplication algorithm for 4-bit integers
• 'mulh' and 'mul' commands to store 128-bit product
• Class-room division method and initialize registers
• Division algorithm initiated
• Conclude results of division algorithm
• Single and double precision floating point extension - RV64F & RV64D
• Normalized scientific notation of decimal and binary number
• Introduction and need of IEEE754 floating point standard
• Sorting problem with existing floating point representation
• Biased floating point representation
• Floating-point standard conclusion
• RV64F and RV64D floating point addition
• Decimal floating-point addition algorithm development
• Binary floating-point addition and significance of RV64D over RV64F

#### Audience Profile

• Anyone who wants to learn world's first Open-Source instruction set architecture RISC-V
• Anyone who wants to learn how to write specifications for RTL coding
• Anyone looking forward to implement their own processor using all open-source tools

#### Prerequisites

• You should have completed RISC-V ISA Part 1a online course
• You should be familiar with boolean addition and subtraction concepts
• You should be familiar with number systems

#### Tools Used

RISC-V GNU Compiler, is the RISC-V C and C++ cross-compiler. It supports two build modes:a generic ELF/Newlib toolchain and a more sophisticated Linux-ELF/glibc toolchain.