MPC555
/
MPC556
CDR MoneT FLASH EEPROM
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
19-36
illustrates the following CENSOR[0:1] transitions:
• T1: Cleared censorship to no censorship
Set CENSOR[0] or CENSOR[1].
• T2: No censorship to information censorship
Set CENSOR[0] and CENSOR[1].
• T3: Information censorship, no censorship or unknown to cleared censorship
clear CENSOR[0:1]. This is done only while the entire CMF array is erased.
• T4: Cleared censorship to information censorship
Set both CENSOR[0] and CENSOR[1].
19.9 Pin Descriptions
The CMF modules use the following pins:
• E
PEE
• V
PP
• V
DDF
• V
SSF
19.9.1 E
PEE
Signal
The EPEE bit monitors the state of the external program/erase enable, E
PEE
pin. E
PEE
has a digital filter that requires two consecutive samples to be equal before the output
of the filter changes. The CMF samples E
PEE
when EHV is asserted and holds the
E
PEE
state until EHV is negated. This is shown in
Figure 19-7 EPEE Digital Filter and Latch
Pin Filter
Output = 1
Pin Filter
Output = 1
Pin Filter
Output = 0
EPEE Pin = 1
@
↑
T2
Pin Filter
Output = 0
EPEE Pin = 0
@
↑
T2
EPEE Pin = 0
@
↑
T2
EPEE Pin = 1
@
↑
T2
EPEE Pin = 0
@
↑
T2
EPEE Pin = 1
@
↑
T2
EPEE Pin’s
Digital Filter
In
Out
Latch
EHV
EPEE
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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