mc9s12xd256 Freescale Semiconductor, Inc, mc9s12xd256 Datasheet - Page 641

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

The following conditions must be satisfied to ensure correct operation of the RAM protection mechanism:
Freescale Semiconductor
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Value stored in RAMXGU must be lower than the value stored in RAMSHL.
Value stored RAMSHL must be lower or equal than the value stored in RAMSHU.
$0F_RAMXGU_FF
$0F_RAMSHU_FF
$0F_RAMSHL_00
CPU access violation
$0F_FFFF
Interrupt Source
Table 17-22. RAM Write Protection Interrupt Vectors
Figure 17-25. RAM Write Protection Scheme
$00_0000
$00_0800
MC9S12XDP512 Data Sheet, Rev. 2.17
Shared Region
Unimplemented
XGATE RAM
Region
2K Registers
CCR Mask
I Bit
Chapter 17 Memory Mapping Control (S12XMMCV2)
Only XGATE is allowed to write
Only CPU is allowed to write
CPU and XGATE are allowed to write
Only CPU is allowed to write
AVIE in RAMWPC
Local Enable
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