MC68HC908AS60ACFN FREESCALE [Freescale Semiconductor, Inc], MC68HC908AS60ACFN Datasheet - Page 88

• Manufacturer Part Number: MC68HC908AS60ACFN
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

EEPROM-2 Memory
7.4.3 EEPROM-2 Program/Erase Protection
The EEPROM has a special feature that designates the 16 bytes of addresses from $06F0 to $06FF to
be permanently secured. This program/erase protect option is enabled by programming the EEPRTCT
bit in the EEPROM-2 Nonvolatile Register (EE2NVR) to a logic zero.
Once the EEPRTCT bit is programmed to 0 for the first time:
7.4.4 EEPROM-2 Block Protection
The 512 bytes of EEPROM-2 are divided into four 128-byte blocks. Each of these blocks can be protected
from erase/program operations by setting the EEBPx bit in the EE2NVR.
ranges for the blocks.
These bits are effective after a reset or a upon read of the EE2NVR register. The block protect
configuration can be modified by erasing/programming the corresponding bits in the EE2NVR register
and then reading the EE2NVR register. Please see
more information.
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Programming and erasing of secured locations $06F0 to $06FF is permanently disabled.
Secured locations $06F0 to $06FF can be read as normal.
Programming and erasing of EE2NVR is permanently disabled.
Bulk and Block Erase operations are disabled for the unprotected locations $0600-$06EF,
$0700-$07FF.
Single byte program and erase operations are still available for locations $0600-$06EF and
$0700-$07FF for all bytes that are not protected by the EEPROM-2 Block Protect EEBPx bits (see
7.4.4 EEPROM-2 Block Protection
Once armed, the protect option is permanently enabled. As a consequence,
all functions in the EE2NVR will remain in the state they were in
immediately before the security was enabled.
Once EEDIVSECD in the EE2DIVHNVR is programmed to 0 and after a
system reset, the EE2DIV security feature is permanently enabled because
the EEDIVSECD bit in the EE2DIVH is always loaded with 0 thereafter.
Once this security feature is armed, erase and program mode are disabled
for EE2DIVHNVR and EE2DIVLNVR. Modifications to the EE2DIVH and
EE2DIVL registers are also disabled. Therefore, be cautious on
programming a value into the EE2DIVHNVR.
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Block Number (EEBPx)
Table 7-1. EEPROM-2 Array Address Blocks
EEBP0
EEBP1
EEBP2
EEBP3
and
7.5.2 EEPROM-2 Array Configuration
NOTE
NOTE
7.5.2 EEPROM-2 Array Configuration Register
Address Range
$0600–$067F
$0680–$06FF
$0700–$077F
$0780–$07FF
Table 7-1
Freescale Semiconductor
shows the address
Register)
for