MPC555CME Freescale Semiconductor, MPC555CME Datasheet - Page 674

• Manufacturer Part Number: MPC555CME
• Description: KIT EVALUATION FOR MPC555
• Manufacturer: Freescale Semiconductor
• Type: Microcontrollerr

Specifications of MPC555CME

• Contents: Module Board, Installation Guide, Power Supply, Cable, Software and more
• Processor To Be Evaluated: MPC555
• Data Bus Width: 32 bit
• Interface Type: RS-232
• For Use With/related Products: MPC555
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

19.5.2 Program Margin Reads
MPC555
USER’S MANUAL
State
S5
The CMF EEPROM provides a program margin read with electrical margin for the pro-
gram state. Program margin reads provide sufficient margin to assure specified data
retention. The program margin read is enabled when SES = 1 and a programming
write has occurred. To increase the access time of the program margin read, the off-
page access time is four clocks instead of the usual two-clock off-page read access
time. The program margin read and subsequent on-page program verify reads return
a one for any bit that has not been completely programmed. Bits that the programming
write left in the non-programmed state return zero when read. Bits that have completed
programming return zero when read and update the data in the programming page
buffer so that no further programming of those bits will occur. The program margin
read occurs during the off-page read. A program margin read must be performed for
all pages that are being programmed after each program pulse.
Current Data in the Pro-
NOTES:
gram Page Buffer
1. 0 = bit needs further programming
2. A “0” read during the margin read means that the bit does NOT need further programming. A “1” means
Program Margin Read Operation:
These reads determines if the state of the bits on
the selected page needs further modification by
the program operation. Once a bit is fully pro-
grammed, the data stored in the program page is
updated. No further programming occurs for that
bit, and the value read is a 0.
While it is not necessary to read all words on a
page to determine if another program pulse needs
to be applied, all pages being programmed must
be read once after each program pulse.
/
1 = bit does not need further programming
the bit needs to be programmed further.
MPC556
Table 19-9 Program Interlock State Descriptions (Continued)
0
0
1
1
Table 19-10 Results of Programming Margin Read
1
Mode
Current State of Bit
Programmed (0)
Programmed (0)
Erased (1)
Erased (1)
CDR MoneT FLASH EEPROM
Rev. 15 October 2000
Data Read During
State
Next
S4
S1
Margin Read
0
1
0
0
T8
T9
Write EHV = 1
Write SES = 0 or a master reset.
2
Transition Requirement
Program Page Buffer
New Data for the
1
0
1
1
MOTOROLA
1
19-22