Rainbow Electronics AT90C8534 - Manual (Page 9)

AT90C8534
9
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 256 bytes of internal data SRAM in the AT90C8534 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 AT90C8534 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).