STRB - Store Register Byte

Syntax

STR[condition]B op1, addr_mode

where:

condition	One of 16 conditions. Refer to Condition Code Status.
op1	register containing source
addr_mode	Addressing Mode 2: Load and Store Word or Unsigned Byte

Description

The STRB instruction takes a byte of data from the LSB of op1 and stores it to an address specified by addr_mode . It also enables PC-relative addressing if used as a base register. The condition needs to be a valid value; else the instruction is rendered an NOP.

Note

A data abort exception is generated if an invalid load or store data access is attempted.

Addressing Mode

Mode 2 - Load and Store Word or Unsigned Byte.

Flags Affected

N	Z	C	V	Q	S	I	F	T
T	T	T	T

Encoding

31		28	27	26	25	24	23	22	21	20	19		16	15		12	11		0
condition			0	1	I	P	U	1	W	0	basereg			op1			addr_mode

Example

1             ;@.text
2             ;@.globl funstr
3             ;@.align 0
4             ;@ **** STRB (Addressing Mode 2) ****
5             ;
6                    AREA example,CODE,READONLY
7
8                    label1
9             ; Store least byte from R8 to an address 28 bytes
10            ; above that held in R10
11   00000000   E5CA801C   STRB   R8, [R10,#28]
12
13            ; Store least byte from R1 to address held in R4
14            ; then increment R4 by an offset given by
15            ; R2 rotated right 8 times
16   00000004   E6C41462   STRB   R1, [R4], R2,ROR #8
17
18            ; Store least byte from R0 to address held in R3
19   00000008   E5C30000   STRB   R0, [R3]

Further Information

See Addressing Mode 2: Load and Store Word or Unsigned Byte