MC68HC908JL8 MOTOROLA [Motorola, Inc], MC68HC908JL8 Datasheet - Page 141

• Manufacturer Part Number: MC68HC908JL8
• Description: Motorola reserves the right to make changes without further notice to any products herein
• Manufacturer: MOTOROLA [Motorola, Inc]

MC68HC908JL8
MOTOROLA
—
Rev. 2.0
When the user dedicates a page of FLASH for data storage, and the size
of the data array defined, each call of the EE_WRTIE routine will
automatically transfer the data in the data array (in RAM) to the next
blank block of locations in the FLASH page. Once a page is filled up, the
EE_WRITE routine automatically erases the page, and starts to reuse
the page again. In the 64-byte page, an 4-byte control block is used by
the routine to monitor the utilization of the page. In effect, only 60 bytes
are used for data storage. (see
are transparent to the user.
When using this routine to store a 3-byte data array, the FLASH page
can be programmed 20 times before the an erase is required. In effect,
the write/erase endurance is increased by 20 times. When a 15-byte
data array is used, the write/erase endurance is increased by 5 times.
Due to the FLASH page size limitation, the data array is limited from 2
bytes to 15 bytes.
The coding example below uses the $EF00–$EE3F page for data
storage. The data array size is 15 bytes, and the bus speed is
4.9152 MHz. The coding assumes the data block is already loaded in
RAM, with the address pointer, FILE_PTR, pointing to the first byte of the
data block.
Freescale Semiconductor, Inc.
PAGE BOUNDARY
PAGE BOUNDARY
For More Information On This Product,
ONE PAGE = 64 BYTES
Figure 9-9. EE_WRITE FLASH Memory Usage
Go to: www.freescale.com
Monitor ROM (MON)
CONTROL: 8 BYTES
F L A S H
DATA ARRAY
DATA ARRAY
DATA ARRAY
Figure
9-9). The page control operations
$XX00, $XX40, $XX80, OR $XXC0
ROM-Resident Routines
Monitor ROM (MON)
Technical Data
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