S3C84E5/C84E9/P84E9INSTRUCTION SET

ADD — Add

ADD

dst,src

Operation:

dst dst + src

 

The source operand is added to the destination operand and the sum is stored in the destination.

 

The contents of the source are unaffected. Two's-complement addition is performed.

Flags:

C: Set if there is a carry from the most significant bit of the result; cleared otherwise.

 

Z: Set if the result is "0"; cleared otherwise.

 

S: Set if the result is negative; cleared otherwise.

 

V: Set if arithmetic overflow occurred, that is, if both operands are of the same sign and the

 

result is of the opposite sign; cleared otherwise.

 

D: Always cleared to "0".

 

H: Set if a carry from the low-order nibble occurred.

Format:

opc

dst src

 

 

opc

src

dst

 

 

 

Bytes

Cycles

Opcode

Addr Mode

 

 

(Hex)

dst

src

2

4

02

r

r

 

6

03

r

lr

3

6

04

R

R

 

 

05

R

IR

opc

dst

src

3

6

06

R

IM

Examples: Given: R1 = 12H, R2 = 03H, register 01H = 21H, register 02H = 03H, register 03H = 0AH:

ADD

R1,R2

R1

= 15H, R2 = 03H

 

 

ADD

R1,@R2

R1

= 1CH, R2 = 03H

 

 

ADD

01H,02H

Register 01H

=

24H, register 02H

=

03H

ADD

01H,@02H

Register 01H

=

2BH, register 02H

=

03H

ADD

01H,#25H

Register 01H

= 46H

 

 

In the first example, the destination working register R1 contains 12H and the source working register R2 contains 03H. The statement "ADD R1,R2" adds 03H to 12H, leaving the value 15H in the register R1.

6-15

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Samsung S3C84E5 user manual ADD Add, Format, Bytes Cycles Opcode