Data EEPROM
ST7LITE20F2 ST7LITE25F2 ST7LITE29F2
Table 4. Row definition
Row / Byte
0123
0
1
...
N
...
30 31
Physical address
00h...1Fh
20h...3Fh
Nx20h...Nx20h+1Fh
Figure 8. Data EEPROM Write operation
Read operation impossible
Read operation possible
E2LAT bit
E2PGM bit
Byte 1 Byte 2
Byte 32
Programming cycle
PHASE 1
Writing data latches
PHASE 2
Waiting E2PGM and E2LAT to fall
Set by USER application
Cleared by hardware
Note:
If a programming cycle is interrupted (by a reset action), the integrity of the data in memory
is not guaranteed.
5.4
Power saving modes
WAIT mode
The DATA EEPROM can enter WAIT mode on execution of the WFI instruction of the
microcontroller or when the microcontroller enters ACTIVE-HALT mode.The DATA EEPROM
will immediately enter this mode if there is no programming in progress, otherwise the DATA
EEPROM will finish the cycle and then enter WAIT mode.
ACTIVE-HALT mode
Refer to WAIT mode.
HALT mode
The DATA EEPROM immediately enters HALT mode if the microcontroller executes the
HALT instruction. Therefore the EEPROM will stop the function in progress, and data may
be corrupted.
5.5
Access error handling
If a read access occurs while E2LAT=1, then the data bus will not be driven.
If a write access occurs while E2LAT=0, then the data on the bus will not be latched.
If a programming cycle is interrupted (by a RESET action), the memory data will not be
guaranteed.
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Doc ID 8349 Rev 5