s3c4510b Samsung Semiconductor, Inc., s3c4510b Datasheet - Page 129

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

S3C4510B
FORMAT 13: ADD OFFSET TO STACK POINTER
OPERATION
This instruction adds a 9-bit signed constant to the stack pointer. The following table shows the THUMB
assembler syntax.
NOTE: The offset specified by #Imm can be up to -/+ 508, but must be word-aligned (ie with bits 1:0 set to 0)
INSTRUCTION CYCLE TIMES
All instructions in this format have an equivalent ARM instruction as shown in Table 3-20. The instruction cycle
times for the THUMB instruction are identical to that of the equivalent ARM instruction.
Examples
S
0
1
ADD SP, #Imm
ADD SP, #-Imm
THUMB Assembler
since the assembler converts #Imm to an 8-bit sign + magnitude number before placing it in field SWord7.
The condition codes are not set by this instruction.
15
1
ADD
ADD
14
0
13
1
SP, #268
SP, #-104
12
1
ADD R13, R13, #Imm Add #Imm to the stack pointer (SP).
SUB R13, R13, #Imm
ARM Equivalent
11
0
Table 3-20. The ADD SP Instruction
10
0
[6:0] 7-bit Immediate Value
[7] Sign Flag
0 = Offset is positive
1 = Offset is negative
Figure 3-42. Format 13
9
0
8
0
; SP (R13): = SP + 268, but don't set the condition codes.
; Note that the THUMB opcode will
; contain 67 as the Word7 value and S = 0.
; SP (R13): = SP - 104, but don't set the condition codes.
; Note that the THUMB opcode will contain
; 26 as the Word7 value and S = 1.
Add #-Imm to the stack pointer (SP).
S
7
6
SWord 7
Action
INSTRUCTION SET
0
3-87