s3c4510b Samsung Semiconductor, Inc., s3c4510b Datasheet - Page 121

• Manufacturer Part Number: s3c4510b
• Description: 16/32-bit Risc Microcontroller
• Manufacturer: Samsung Semiconductor, Inc.

S3C4510B
FORMAT 8: LOAD/STORE SIGN-EXTENDED BYTE/HALF-WORD
OPERATION
These instructions load optionally sign-extended bytes or half-words, and store half-words. The THUMB
assembler syntax is shown below.
L
0
0
1
1
B
0 STRH Rd, [Rb, Ro]
1 LDRH Rd, [Rb, Ro]
0 LDSB Rd, [Rb, Ro]
1 LDSH Rd, [Rb, Ro]
THUMB Assembler
15
0
14
1
13
0
12
1
STRH Rd, [Rb, Ro]
LDRH Rd, [Rb, Ro]
LDRSB Rd, [Rb, Ro] Load sign-extended byte:
LDRSH Rd, [Rb, Ro] Load sign-extended half-word:
Table 3-15. Summary of format 8 instructions
ARM Equivalent
11
H
10
S
[2:0] Destination Register
[5:3] Base Register
[8:6] Offset Register
[10] Sign-Extended Flag
0 = Operand not sing-extended
1 = Operand sing-extended
[11] H Flag
Figure 3-37. Format 8
9
1
8
Store half-word:
Add Ro to base address in Rb. Store bits 0–15 of Rd at
the resulting address.
Load half-word:
Add Ro to base address in Rb. Load bits 0–15 of Rd from
the resulting address, and set bits 16-31 of Rd to 0.
Add Ro to base address in Rb. Load bits 0–7 of Rd from
the resulting address, and set bits 8-31 of Rd to bit 7.
Add Ro to base address in Rb. Load bits 0–15 of Rd from
the resulting address, and set bits 16-31 of Rd to bit 15.
Ro
6
5
Rb
Action
3
2
INSTRUCTION SET
Rd
0
3-79