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Program and data addressing modes, Register direct, single register rd, Register direct, two registers rd and rr – Rainbow Electronics AT90LS8535 User Manual

Page 12: I/o direct

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AT90S/LS8535

1041H–11/01

Program and Data
Addressing Modes

The AT90S8535 AVR RISC microcontroller supports powerful and efficient addressing
modes for access to the program memory (Flash) and data memory (SRAM, register file
and I/O memory). This section describes the different addressing modes supported by
the AVR architecture. In the figures, OP means the operation code part of the instruction
word. To simplify, not all figures show the exact location of the addressing bits.

Register Direct, Single
Register Rd

Figure 9. Direct Single Register Addressing

The operand is contained in register d (Rd).

Register Direct, Two Registers
Rd And Rr

Figure 10. Direct Register Addressing, Two Registers

Operands are contained in register r (Rr) and d (Rd). The result is stored in register d
(Rd).

I/O Direct

Figure 11. I/O Direct Addressing

Operand address is contained in six bits of the instruction word. n is the destination or
source register address.