Data indirect with pre- decrement, Data indirect with post- increment, Constant addressing using the lpm instruction – Rainbow Electronics AT90LS8535 User Manual

Page 14

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14

AT90S/LS8535

1041H–11/01

Data Indirect with Pre-
decrement

Figure 15. Data Indirect Addressing with Pre-decrement

The X-, Y-, or the Z-register is decremented before the operation. Operand address is
the decremented contents of the X-, Y-, or the Z-register.

Data Indirect with Post-
increment

Figure 16. Data Indirect Addressing with Post-increment

The X-, Y-, or the Z-register is incremented after the operation. Operand address is the
content of the X-, Y-, or the Z-register prior to incrementing.

Constant Addressing Using
the LPM Instruction

Figure 17. Code Memory Constant Addressing

Constant byte address is specified by the Z-register contents. The 15 MSBs select word
address (0 - 4K), the LSB selects low byte if cleared (LSB = 0) or high byte if set (LSB =
1).

Data Space

$0000

$025F

X, Y OR Z - REGISTER

0

15

-1

Data Space

$0000

$025F

X, Y OR Z - REGISTER

0

15

1

$FFF

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