mc68hc908gt8 Freescale Semiconductor, Inc, mc68hc908gt8 Datasheet - Page 43

• Manufacturer Part Number: mc68hc908gt8
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

2.6.5 Flash Program/Read Operation
Programming of the Flash memory is done on a row basis. A row consists of 32 consecutive bytes starting
from addresses $XX00, $XX20, $XX40, $XX60, $XX80, $XXA0, $XXC0, or $XXE0. Use the following
step-by-step procedure to program a row of Flash memory
Figure 2-4
This program sequence is repeated throughout the memory until all data is programmed.
Freescale Semiconductor
10. Clear the PGM bit
11. Wait for time, t
12. Clear the HVEN bit.
13. After time, t
1. The time between each Flash address change, or the time between the last Flash address programmed to clearing PGM
1. Set the PGM bit. This configures the memory for program operation and enables the latching of
2. Read the Flash block protect register.
3. Write any data to any Flash location within the address range desired.
4. Wait for a time, t
5. Set the HVEN bit.
6. Wait for a time, t
7. Write data to the Flash address being programmed
8. Wait for time, t
9. Repeat step 7 and 8 until all desired bytes within the row are programmed.
bit, must not exceed the maximum programming time, t
address and data for programming.
is a flowchart of the programming algorithm.
performed in the order as shown, but other unrelated operations may occur
between the steps.
A mass erase will erase the internal oscillator trim values at $FF80 and
$FF81.
Only bytes which are currently $FF may be programmed.
The COP register at location $FFFF should not be written between steps
5-12, when the HVEN bit is set. Since this register is located at a valid Flash
address, unpredictable behavior may occur if this location is written while
HVEN is set.
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 shown, other unrelated operations may occur
between the steps. Do not exceed t
Characteristics.
RCV
MC68HC908GT16 • MC68HC908GT8 • MC68HC08GT16 Data Sheet, Rev. 5.0
PROG
NVH
(typical 1 μs), the memory can be accessed in read mode again.
NVS
PGS
(1)
(minimum 5 μs).
.
(minimum 30 μs).
(minimum 10 μs).
(minimum 5 μs).
CAUTION
NOTE
NOTE
NOTE
PROG
PROG
maximum.
maximum, see
(1)
.
20.20 Memory
Flash Memory
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