SB

Store Byte

SB rs2, offset(rs1)

Stores the lowest 8 bits of a register to memory.

Encoding

Binary Layout

imm12hi

31:25

rs2

24:20

rs1

19:15

000

14:12

imm12lo

11:7

0100011

6:0

 

Format S-Type

Opcode 0x00000023

Extension RV32I

Operands

• rs2
  Source
• rs1
  Base Address
• offset
  Offset

Example

SB x5, 0(x10)

// Store low byte of x5 to address in x10.

Related

More in RV32I

Reference

View in RISC-V Unprivileged ISA Specification ↗ RISC-V ISA Manual

Description

SB stores the least-significant byte of rs2 to memory at address rs1+sext(offset).

Operation

M[R[rs1] + sext(offset)][7:0] = R[rs2][7:0];