MC9RS08KA8RM Datasheet, PDF (31/190 Pages) Freescale Semiconductor, Inc – MC9RS08KA8 Features

Chapter 4 Memory
first page ($0000–$00FF) can be read/written via register D[X]. Figure 4-2 shows the relationship between
D[X] and register X. For example, in HC08/S08 syntax latex is comparable to lda D[X] in RS08 coding
when register X has been programmed with the index value.
The physical location of $000E is in RAM. Accessing the location through D[X] returns $000E RAM
content when register X contains $0E. The physical location of $000F is register X, itself. Reading the
location through D[X] returns register X content. Writing to the location modifies register X.
$0000
$000E
$000F
D[X]
Register X
Address indicated in
Register X
Content of this location can be accessed via D[X]
$00FF
$0100
Register X can specify
any location between
$0000–$00FF
Figure 4-2. Indirect Addressing Registers
4.4 RAM and Register Addresses and Bit Assignments
Use short and direct addressing mode instructions to read and write to the fast access RAM area. For tiny
addressing mode instructions, the operand is encoded with the opcode to a single byte.
MC9RS08KA8 Series Reference Manual, Rev. 3
Freescale Semiconductor
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