AND

And Accumulator with Memory
Tags:

AND performs a logical And of the value in the accumulator with that of the memory location with the result stored in the accumulator.

The result will be each bit in the accumulator will be set ONLY if that same bit was set in the original accumulator value and the memory. If the bits were different then the resultant bit will be 0.

AND truth table
Second Operand
First Operand01
000
101

For 8-bit processors n has the value of bit 7 and v the value of bit 6 of the memory location.

For 16-bit processors, when m=0, n has the value of bit 15 and v the value of bit 14 of the memory location.

Second it performs a logical AND of the memory and the accumulator. If the result is zero the z flag is set.

In both operations, the contents of the accumulator and memory are not modified.

Flags Affected
Flags
n-----z-
nSet if most significant bit of result is set
zSet if result is zero, otherwise clear
Instructions
SyntaxOpcode Available on: # of # of Addressing Mode
(hex) 6502 65C02 65816 bytes cycles
AND #const29 x x x 21 22 Immediate
AND addr2D x x x 3 42 Absolute
AND long2F x 4 52 Absolute Long
AND dp25 x x x 2 32, 3 Direct Page
AND (dp)32 x x 2 52, 3 Direct Page Indirect
AND [dp]27 x 2 62, 3 Direct Page Indirect Long
AND addr,X3D x x x 3 42, 4 Absolute Indexed X
AND long,X3F x 4 52 Absolute Long Indexed X
AND addr,Y39 x x x 3 42, 4 Absolute Indexed Y
AND dp,X35 x x x 2 42, 3 Direct Page Indexed X
AND (dp,X)21 x x x 2 62, 3 Direct Page Indexed Indirect X
AND (dp),Y31 x x x 2 52, 3, 4 Direct Page Indirect Indexed Y
AND [dp],Y37 x 2 62, 3 Direct Page Indirect Long Indexed Y
AND sr,S23 x 2 42 Stack Relative
AND (sr,S),Y33 x 2 72 Stack Relative Indirect Indexed Y

Notes:

  1. 65816: Add 1 byte if m=0 (16-bit memory/accumulator)
  2. 65816: Add 1 cycle if m=0 (16-bit memory/accumulator)
  3. 65816: Add 1 cycle if low byte of Direct Page register is not 0
  4. Add 1 cycle if adding index crosses a page boundary
Last modified November 5, 2021: Add instruction categories (6b74ff9)