MPC555
/
MPC556
CDR MoneT FLASH EEPROM
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
19-40
19.10.3 Emulation Operation
The CMF EEPROM supports externally mapped access for emulation operation.
When the SIU indicates an externally mapped access to the CMF EEPROM, the CMF
does not respond to the address, even though it may be a valid CMF access. Refer to
10.6 Dual Mapping of the Internal Flash EEPROM Array
for details.
19.11 Disabling the CMF Module
The CMF EEPROM can be disabled when the internal memories are disabled. Dis-
abling the internal memories is controlled by the FLEN bit (bit 20) in the USIU internal
memory map register. The default reset enable/disable state of the internal memories
is user defined with the reset configuration word bit 20.
CAUTION
The reset configuration word from an erased CMF must be generat-
ed external to the CMF, i.e., from the default reset configuration word
off the external reset configuration word. See
EHV is reset to 0 when the CMF is disabled and can not be set until the CMF is en-
abled, see section
19.7.8 Controlling the Program/Erase Voltage
When disabled,
the power used by the CMF is reduced.
NOTE
Although the program and erase operations can be suspended (EHV
= 0) by disabling the internal memory, it is not recommended that pro-
gram or erase be suspended in this manner.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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