Nintendo NES-001 User Guide - Page 42
E.6 Implied, E.7 Accumulator, E.8 Immediate
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Figure E-5. Indirect addressing. E.6 Implied Many instructions do not require access to operands stored in memory. Examples of implied instructions are CLD (Clear Decimal Mode) and NOP (No Operation). E.7 Accumulator Some instructions operate directly on the contents of the accumulator. The only instructions to use this addressing mode are the shift instructions, ASL (Arithmetic Shift Left), LSR (Logical Shift Right), ROL (Rotate Left) and ROR (Rotate Right). E.8 Immediate Instructions which use immediate addressing operate directly on a constant supplied as an operand to the instruction. Immediate instructions are indicated by prefacing the operand with #, for example AND #$12. Figure E-6. Immediate addressing. 42
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Figure E-5. Indirect addressing.
E.6 Implied
Many instructions do not require access to operands stored in memory. Examples of implied
instructions are CLD (Clear Decimal Mode) and NOP (No Operation).
E.7 Accumulator
Some instructions operate directly on the contents of the accumulator. The only instructions
to use this addressing mode are the shift instructions, ASL (Arithmetic Shift Left), LSR
(Logical Shift Right), ROL (Rotate Left) and ROR (Rotate Right).
E.8 Immediate
Instructions which use immediate addressing operate directly on a constant supplied as an
operand to the instruction. Immediate instructions are indicated by prefacing the operand
with #, for example AND #$12.
Figure E-6. Immediate addressing.