AT90LS4433-4AI datasheet(12/126 Pages) ATMEL

12 / 126 page

AT90S/LS4433

1042H–AVR–04/03

The direct addressing reaches the entire data space. The Indirect with Displacement

mode features 63 address locations reached from the base address given by the Y- or

Z-register.

When using register indirect addressing modes with automatic pre-decrement and post-

increment, the address registers X, Y, and Z are decremented and incremented.

The 32 general purpose working registers, 64 I/O Registers and the 128 bytes of inter-

nal data SRAM in the AT90S4433 are all accessible through all these addressing

modes.

See the next section for a detailed description of the different addressing modes.

Program and Data

Addressing Modes

The AT90S4433 AVR RISC microcontroller supports powerful and efficient addressing

modes for access to the Flash Program memory, SRAM, Register File, and I/O data

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.

Figure 10. Direct Single Register Addressing

The operand is contained in register d (Rd).

Rd and Rr

Figure 11. Direct Register Addressing, Two Registers

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

(Rd).

AT90LS4433-4AI Datasheet(PDF) 12 Page - ATMEL Corporation