MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 405

• Manufacturer Part Number: MC68HC12
• Description: The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
• Manufacturer: MOTOROLA [Motorola, Inc]

20.4.4.2 Disabling the BDM lockout
20.4.5 BDM Registers
MC68HC912DT128A — Rev 4.0
MOTOROLA
NOTE:
Disabling the BDM lockout is only possible in special modes
(SMODN=0) except in special single chip. Follow the same steps as for
enabling the BDM lockout, but erase the SHADOW word.
At the next reset, the high byte of SHADOW word is loaded into the
EEMCR register. NOBDML bit in EEMCR will be set and BDM becomes
operational.
When the BDM lockout is enabled it is not possible to run code from the
reset vector in special single chip mode.
Seven BDM registers are mapped into the standard 64-Kbyte address
space when BDM is active. Mapping is shown in
The content of the INSTRUCTION register is determined by the type of
background command being executed.The STATUS register indicates
BDM operating conditions.The SHIFT register contains data being
received or transmitted via the serial interface. The ADDRESS register
4. Protect the SHADOW word by setting SHPROT bit in EEPROT
SHADOW word (location $0FC0); otherwise some regular
EEPROM array locations will not be visible. At the next reset, the
high byte of the SHADOW word is loaded into the EEMCR
register. NOBDML bit in EEMCR will be cleared and BDM will not
be operational.
register.
$FF02 – $FF03
$FF04 – $FF05
Development Support
Address
$FF00
$FF01
$FF06
Table 20-4. BDM registers
BDM CCR Holding Register
BDM Instruction Register
BDM Address Register
BDM Status Register
BDM Shift Register
Register
Table
Background Debug Mode
Development Support
20-4.
Technical Data
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