Laptop User Manual

ARM INSTRUCTION SET S3C2440A RISC MICROPROCESSOR
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ASSEMBLER SYNTAX
<LDR|STR>{cond}<H|SH|SB> Rd,<address>
LDR Load from memory into a register
STR Store from a register into memory
{cond} Two-character condition mnemonic. See Table 3-2..
H Transfer halfword quantity
SB Load sign extended byte (Only valid for LDR)
SH Load sign extended halfword (Only valid for LDR)
Rd An expression evaluating to a valid register number.
<address> can be:
1 An expression which generates an address:
The assembler will attempt to generate an instruction using the PC as a base and a
corrected immediate offset to address the location given by evaluating the expression.
This will be a PC relative, pre-indexed address. If the address is out of range, an error will
be generated.
2 A pre-indexed addressing specification:
[Rn] offset of zero
[Rn,<#expression>]{!} offset of <expression> bytes
[Rn,{+/-}Rm]{!} offset of +/- contents of index register
3 A post-indexed addressing specification:
[Rn],<#expression> offset of <expression> bytes
[Rn],{+/-}Rm offset of +/- contents of index register.
4 Rn and Rm are expressions evaluating to a register number. If Rn is R15 then the
assembler will subtract 8 from the offset value to allow for ARM920T pipelining. In this
case base write-back should not be specified.
{!} Writes back the base register (set the W bit) if ! is present.