Operations:

Syntax:

Operation:

Operands:

Program Counter:

Opcode

Comment

Stack

OR Rd,Rr

Rd = Rd OR Rr

0 <= d <= 31, 0 <= r <= 31

PC = PC + 1

001010rdddddrrrr

Description

Performs the logical OR between the contents of register Rd and register Rr, and places the result in the destination register Rd.

Status Register (SREG) and Boolean Formula

I

–

T

–

H

–

S

⇔

N XOR V, for signed tests.

V

0

0

Cleared.

N

⇔

R7

Set if MSB of the result is set; cleared otherwise.

Z

⇔

~R7 AND ~R6 AND ~R5 AND ~R4 AND ~R3 AND ~R2 AND ~R1 AND ~R0

Set if the result is 0x00; cleared otherwise.

C

–

R (Result)

R (Result) equals Rd after the operation.

Example: 

      or    r15,r16   ; Do bitwise or between registers
      bst   r15,6     ; Store bit 6 of r15 in T bit
      brts  ok        ; Branch if T bit set
      ...
ok: 
      nop             ; Branch destination (do nothing)

Words

1 (2 bytes)

Table Cycles

Name

Cycles

AVRe

1

AVRxm

1

AVRxt

1

AVRrc

1