Datasheet

Memory Mapping Control (S12XMMCV4)

S12XS Family Reference Manual, Rev. 1.13

Freescale Semiconductor 139

3.3.2.7 Data FLASH Page Index Register (EPAGE)

Read: Anytime

Write: Anytime

These eight index bits are used to page 1KB blocks into the Data FLASH page window located in the local

(CPU or BDM) memory map from address 0x0800 to address 0x0BFF (see Figure 3-16). This supports

accessing up to 256KB of Data FLASH (in the Global map) within the 64KB Local map. The Data FLASH

page index register is effectively used to construct paged Data FLASH addresses in the Local map format.

Figure 3-16. EPAGE Address Mapping

Address: 0x0017

76543210

EP7 EP6 EP5 EP4 EP3 EP2 EP1 EP0

Reset 11111110

Figure 3-15. Data FLASH Page Index Register (EPAGE)

Table 3-9. EPAGE Field Descriptions

Field Description

7–0

EP[7:0]

Data FLASH Page Index Bits 7–0 — These page index bits are used to select which of the 256 Data FLASH

array pages is to be accessed in the Data FLASH Page Window.

Bit16

Bit0

Bit9

Address [9:0]

EPAGE Register [7:0]

Global Address [22:0]

Bit10

Bit17

00 100

Address: CPU Local Address

or BDM Local Address