mc9s12xd256 Freescale Semiconductor, Inc, mc9s12xd256 Datasheet - Page 625

• Manufacturer Part Number: mc9s12xd256
• Description: Hcs12x Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

The reset value of $FD ensures that there is a linear RAM space available between addresses $1000 and
$3FFF out of reset.
The fixed 4K page from $2000–$2FFF of RAM is equivalent to page 254 (page number $FE).
The fixed 4K page from $3000–$3FFF of RAM is equivalent to page 255 (page number $FF).
Freescale Semiconductor
RP[7:0]
Field
7–0
RAM Page Index Bits 7–0 — These page index bits are used to select which of the 256 RAM array pages is to
be accessed in the RAM Page Window.
Because RAM page 0 has the same global address as the register space, it is
possible to write to registers through the RAM space when RPAGE = $00.
0
0
0
Figure 17-12. RPAGE Address Mapping
Table 17-11. RPAGE Field Descriptions
Bit19
MC9S12XDP512 Data Sheet, Rev. 2.17
Global Address [22:0]
Bit18
RPAGE Register [7:0]
NOTE
Description
Bit12
Address: CPU Local Address
Chapter 17 Memory Mapping Control (S12XMMCV2)
Bit11
or BDM Local Address
Address [11:0]
Bit0
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