mc68hc908qf4 Freescale Semiconductor, Inc, mc68hc908qf4 Datasheet - Page 31

• Manufacturer Part Number: mc68hc908qf4
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

2.6.2 FLASH Page Erase Operation
MC68HC908QF4 — Rev. 1.0
MOTOROLA
NOTE:
ERASE — Erase Control Bit
PGM — Program Control Bit
Use the following procedure to erase a page of FLASH memory. A page consists
of 64 consecutive bytes starting from addresses $XX00, $XX40, $XX80, or $XXC0.
The 48-byte user interrupt vectors area also forms a page. Any FLASH memory
page can be erased alone.
Programming and erasing of FLASH locations cannot be performed by code being
executed from the FLASH memory. While these operations must be performed in
the order as shown, but other unrelated operations may occur between the steps.
In applications that need up to 10,000 program/erase cycles, use the 4 ms page
erase specification to get improved long-term reliability. Any application can use
this 4 ms page erase specification. However, in applications where a FLASH
location will be erased and reprogrammed less than 1000 times, and speed is
important, use the 1 ms page erase specification to get a lower minimum erase
time.
10. After time, t
1. Set the ERASE bit and clear the MASS bit in the FLASH control register.
2. Read the FLASH block protect register.
3. Write any data to any FLASH location within the address range of the block
4. Wait for a time, t
5. Set the HVEN bit.
6. Wait for a time, t
7. Clear the ERASE bit.
8. Wait for a time, t
9. Clear the HVEN bit.
This read/write bit configures the memory for erase operation. ERASE is
interlocked with the PGM bit such that both bits cannot be equal to 1 or set to 1
at the same time.
This read/write bit configures the memory for program operation. PGM is
interlocked with the ERASE bit such that both bits cannot be equal to 1 or set to
1 at the same time.
1 = Erase operation selected
0 = Erase operation unselected
1 = Program operation selected
0 = Program operation unselected
to be erased.
again.
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
RCV
(typical 1 µs), the memory can be accessed in read mode
NVS
Erase
NVH
Memory
(minimum 10 µs).
(minimum 5 µs).
(minimum 1 ms or 4 ms).
FLASH Memory (FLASH)
Data Sheet
Memory
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