AN1836 Motorola / Freescale Semiconductor, AN1836 Datasheet - Page 15

• Manufacturer Part Number: AN1836
• Description: FLASH Programming for Motorola MC68HC912 Microcontrollers
• Manufacturer: Motorola / Freescale Semiconductor

Erasing the FLASH Array
AN1836
MOTOROLA
This sequence demonstrates the recommended procedure for erasing
the FLASH EEPROM. The V
prior to executing step 4 the first time.
The flowchart in
sequence.
10. If all of the FLASH EEPROM locations are erased, repeat the
11. Read the entire array to ensure that the FLASH EEPROM is
12. Clear LAT.
13. Turn off V
1. Turn on V
2. Set the LAT bit and ERAS bit to configure the FLASH EEPROM
3. Write to any valid address in the FLASH array. This allows the
4. Apply erase voltage by setting ENPE.
5. Delay for a single erase pulse, t
6. Remove erase voltage by clearing ENPE.
7. Delay while high voltage is turning off, t
8. Read the entire array to ensure that the FLASH EEPROM is
9. If all of the FLASH EEPROM locations are not erased, repeat
for erasing.
erase voltage to be turned on; the data written and the address
written are not important. The boot block will be erased only if the
control bit BOOTP is negated.
erased.
steps 4 through 7 until either the remaining locations are erased
or until the maximum erase pulses have been applied, n
same number of pulses as required to erase the array. This
provides 100 percent erase margin.
erased.
FP
FP
Figure 8
. Apply program/erase voltage to the V
. Reduce voltage on V
demonstrates the recommended erase
FP
pin voltage must be at the proper level
EPULSE
FP
pin to V
.
VERASE
Erasing the FLASH Array
DD
.
.
FP
Application Note
pin.
EP
.
15