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Constant addressing using the lpm instruction, Indirect program addressing, ijmp and icall, Relative program addressing, rjmp and rcall – Rainbow Electronics AT90LS4433 User Manual

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AT90S/LS4433

1042G–AVR–09/02

Constant Addressing Using
the LPM Instruction

Figure 18. Code Memory Constant Addressing

Constant byte address is specified by the Z-register contents. The 15 MSBs select word
address (0 - 2K), the LSB selects Low Byte if cleared (LSB = 0) or High Byte if set
(LSB = 1).

Indirect Program Addressing,
IJMP and ICALL

Figure 19. Indirect Program Memory Addressing

Program execution continues at address contained by the Z-register (i.e., the PC is
loaded with the contents of the Z-register).

Relative Program Addressing,
RJMP and RCALL

Figure 20. Relative Program Memory Addressing

Program execution continues at address PC + k + 1. The relative address k is from
-2048 to 2047.

$7FF

$000

PROGRAM MEMORY

$7FF

$000

PROGRAM MEMORY

$7FF

$000

PROGRAM MEMORY

+1