SAM3N00A Atmel Corporation, SAM3N00A Datasheet - Page 94

• Manufacturer Part Number: SAM3N00A
• Manufacturer: Atmel Corporation

10.12.4
10.12.4.1
10.12.4.2
10.12.4.3
10.12.4.4
10.12.4.5
94
STRBTEQ
LDRHT
SAM3N
LDR and STR, unprivileged
Syntax
Operation
Restrictions
Condition flags
Examples
R4, [R7]
R2, [R2, #8]
Load and Store with unprivileged access.
where:
op
type is one of:
cond
Rt
Rn
offset
These load and store instructions perform the same function as the memory access instructions
with immediate offset, see
these instructions have only unprivileged access even when used in privileged software.
When used in unprivileged software, these instructions behave in exactly the same way as nor-
mal memory access instructions with immediate offset.
In these instructions:
These instructions do not change the flags.
• Rn must not be PC
• Rt must not be SP and must not be PC.
op{type}T{cond} Rt, [Rn {, #offset}]
LDR
STR
B
SB
H
SH
-
; Conditionally store least significant byte in
; R4 to an address in R7, with unprivileged access
; Load halfword value from an address equal to
; sum of R2 and 8 into R2, with unprivileged access
is one of:
Load Register.
Store Register.
unsigned byte, zero extend to 32 bits on loads.
signed byte, sign extend to 32 bits (LDR only).
unsigned halfword, zero extend to 32 bits on loads.
signed halfword, sign extend to 32 bits (LDR only).
omit, for word.
is an optional condition code, see
is the register to load or store.
is the register on which the memory address is based.
is an offset from Rn and can be 0 to 255.
If offset is omitted, the address is the value in Rn.
“LDR and STR, immediate offset” on page
“Conditional execution” on page
; immediate offset
89. The difference is that
11011A–ATARM–04-Oct-10
84.