Freescale Semiconductor, Inc.
Operating Modes and Resource Mapping
5.5.2 RAM Mapping
The 68HC(9)12D60 has 2K byte of fully static RAM that is used for
storing instructions, variables, and temporary data during program
execution. After reset, RAM addressing begins at location $0000 but can
be assigned to any 2K byte boundary within the standard 64K byte
address space. Mapping of internal RAM is controlled by five bits in the
INITRM register.
After reset, the first 512 bytes of RAM have their access inhibited by the
presence of the register address space. After initial MCU configuration,
it is recommended to map the register space at location $0800.
Bit 7
6
5
RAM13
0
4
RAM12
0
3
RAM11
0
2
0
0
1
0
0
Bit 0
RAM15
0
RAM14
0
0
0
RESET:
INITRM — Initialization of Internal RAM Position Register
$0010
RAM[15:11] — Internal RAM map position
These bits specify the upper five bits of the 16-bit RAM address.
Normal modes: write once; special modes: write anytime. Read
anytime.
Advance Information
82
68HC(9)12D60 — Rev 4.0
Operating Modes and Resource Mapping
MOTOROLA
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