MC68HC908AB32 MOTOROLA [Motorola, Inc], MC68HC908AB32 Datasheet - Page 73

• Manufacturer Part Number: MC68HC908AB32
• Description: HCMOS Microcontroller Unit
• Manufacturer: MOTOROLA [Motorola, Inc]

5.9 EEPROM Programming and Erasing
MC68HC908AB32
MOTOROLA
NOTE:
—
Rev. 1.0
These bits are effective after a reset or a read to EENVR register. The
block protect configuration can be modified by erasing/programming the
corresponding bits in the EENVR register and then reading the EENVR
register.
The unprogrammed or erased state of an EEPROM bit is a logic 1. The
factory default for the EEPROM array is $FF for all bytes.
The programming operation changes an EEPROM bit from logic 1 to
logic 0 (programming cannot change a bit from logic 0 to a logic 1). In a
single programming operation, the minimum EEPROM programming
size is zero bits; the maximum is eight bits (one byte).
The erase operation changes an EEPROM bit from logic 0 to logic 1. In
a single erase operation, the minimum EEPROM erase size is one byte;
the maximum is the entire EEPROM array.
For each EEPROM byte, the write/erase endurance is 10,000 cycles.
One write/erase cycle is defined as: a maximum of eight programming
operations on the same byte followed by an erase operation of the that
byte . Therefore, it is possible to program a byte, bit by bit to logic 0
before requiring an erase on that byte.
Although programming a bit (from 0 or 1) with a logic 1 does not change
the state of that bit, it is still regarded as a programming operation. That
is, if the same byte is programmed eight times (with any value), that byte
must be erased before it can be successfully programmed again.
Freescale Semiconductor, Inc.
For More Information On This Product,
Block Number (EEBPx)
Go to: www.freescale.com
Table 5-1. EEPROM Array Address Blocks
EEBP0
EEBP1
EEBP2
EEBP3
EEPROM
EEPROM Programming and Erasing
Address Range
$0880–$08FF
$0980–$09FF
$0800–$087F
$0900–$097F
Technical Data
EEPROM
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