Intel Embedded Microcontroller ADD Rm,@DRk Binary Mode Source Mode Bytes4 States4 Encoding, Flags

Models: Embedded Microcontroller 8XC251SP 8XC251SA 8XC251SQ 8XC251SB

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8XC251SA, SB, SP, SQ USER’S MANUAL

ADD Rm,@DRk

Binary Mode Source Mode

Bytes:4

States:4

[Encoding]

0 0 1 0

1 1 1 0

 

 

3

3

u u u u

1 0 1 1

 

 

s s s s

0 0 0 0

Hex Code in:

Binary Mode = [A5][Encoding]

 

Source Mode = [Encoding]

Operation:

ADD

 

(Rm) (Rm) + ((DRk))

 

 

ADDC A,<src>

 

Function:

Add with carry

Description:

Simultaneously adds the specified byte variable, the CY flag, and the accumulator contents,

 

leaving the result in the accumulator. If there is a carry out of bit 7 (CY), the CY flag is set; if

 

there is a carry out of bit 3 (AC), the AC flag is set. When adding unsigned integers, the CY

 

flag indicates that an overflow occurred.

 

If there is a carry out of bit 6 but not out of bit 7, or a carry out of bit 7 but not bit 6, the OV

 

flag is set. When adding signed integers, the OV flag indicates a negative number produced

 

as the sum of two positive operands, or a positive sum from two negative operands.

 

Bit 6 and bit 7 in this description refer to the most significant byte of the operand (8, 16, or 32

 

bit)

 

Four source operand addressing modes are allowed: register, direct, register-indirect, and

 

immediate.

Flags:

CY

AC

OV

N

Z

 

 

 

 

 

 

 

 

 

 

Example: The accumulator contains 0C3H (11000011B), register 0 contains 0AAH (10101010B), and the CY flag is set. After executing the instruction

ADDC A,R0

the accumulator contains 6EH (01101110B), the AC flag is clear, and the CY and OV flags are set.

Variations

ADDC A,#data

 

 

 

Binary Mode

Source Mode

Bytes:

2

2

States:

1

1

A-32

 

 

Page 284
Image 284
Intel Embedded Microcontroller ADD Rm,@DRk Binary Mode Source Mode Bytes4 States4 Encoding, Addc A,src Function, Flags