mc68hc912bc32 Freescale Semiconductor, Inc, mc68hc912bc32 Datasheet - Page 81

• Manufacturer Part Number: mc68hc912bc32
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

5.4.4 EEPROM Initialization Register
The MCU has 768 bytes of EEPROM which are activated by the EEON bit in the EEPROM initialization
register (INITEE).
Mapping of internal EEPROM is controlled by four bits in the INITEE register. After reset, EEPROM
address space begins at location $0D00 but can be mapped to any 4-Kbyte boundary within the standard
64-Kbyte address space.
Read: anytime
Write: varies from bit to bit
EE15–EE12 — Internal EEPROM Position Bits
EEON — EEPROM On Bit
5.4.5 Miscellaneous Mapping Control Register
Additional mapping controls are available that can be used in conjunction with FLASH EEPROM/ROM
and memory expansion.
The 32-Kbyte FLASH EEPROM/ROM can be mapped to either the upper or lower half of the 64-Kbyte
address space. When mapping conflicts occur, registers, RAM, and EEPROM have priority over FLASH
EEPROM.
To use memory expansion, the part must be operated in one of the expanded modes.
Freescale Semiconductor
These bits specify the upper four bits of the 16-bit EEPROM address. Write once in normal modes or
anytime in special modes.
EEON allows read access to the EEPROM array. EEPROM control registers can be accessed and
EEPROM locations can be programmed or erased regardless of the state of EEON.
EEON is forced to 1 in single-chip modes.
Write only in expanded and peripheral modes.
1 = EEPROM in memory map
0 = EEPROM removed from memory map
Address: $0012
Only the MC68HC912B32 contains FLASH EEPROM. The
MC68HC12BE32 contains ROM.
Reset:
Read:
Write:
EE15
Bit 7
0
Figure 5-4. EEPROM Initialization Register (INITEE)
EE14
6
0
M68HC12B Family Data Sheet, Rev. 9.1
EE13
5
0
NOTE
EE12
4
0
3
0
0
2
0
0
Mode and Resource Mapping Registers
1
0
0
EEON
Bit 0
1
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