Datasheet

Chapter 3 Memory Mapping Control (S12XMMCV4)
MC9S12XE-Family Reference Manual Rev. 1.25
Freescale Semiconductor 209
Figure 3-18. BDMGPR Address Mapping
3.4.2.3 Implemented Memory Map
The global memory spaces reserved for the internal resources (RAM, EEE, and FLASH) are not
determined by the MMC module. Size of the individual internal resources are however fixed in the design
of the device cannot be changed by the user. Please refer to the Device User Guide for further details.
Figure 3-19 and Table 3-17 show the memory spaces occupied by the on-chip resources. Please note that
the memory spaces have fixed top addresses.
When the device is operating in expanded modes except emulation single-chip mode, accesses to global
addresses which are not occupied by the on-chip resources (unimplemented areas or external memory
space) result in accesses to the external bus (see Figure 3-19).
Table 3-17. Global Implemented Memory Space
Internal Resource $Address
RAM RAM_LOW = 0x10_0000 minus RAMSIZE
(1)
1. RAMSIZE is the hexadecimal value of RAM SIZE in bytes
FLASH FLASH_LOW = 0x80_0000 minus FLASHSIZE
(2)
2. FLASHSIZE is the hexadecimal value of FLASH SIZE in bytes
Bit16 Bit0Bit15Bit22
BDM Local Address
BDMGPR Register [6:0]
Global Address [22:0]
Bit16 Bit0Bit15Bit22
CPU Local Address
BDMGPR Register [6:0]
Global Address [22:0]
BDM HARDWARE COMMAND
BDM FIRMWARE COMMAND