ST7FLITE02 STMICROELECTRONICS [STMicroelectronics], ST7FLITE02 Datasheet - Page 15

• Manufacturer Part Number: ST7FLITE02
• Description: 8-BIT MICROCONTROLLER WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

FLASH PROGRAM MEMORY (Cont’d)
4.5 Memory Protection
There are two different types of memory protec-
tion: Read Out Protection and Write/Erase Protec-
tion which can be applied individually.
4.5.1 Read out Protection
Readout protection, when selected provides a pro-
tection against program memory content extrac-
tion and against write access to Flash memory.
Even if no protection can be considered as totally
unbreakable, the feature provides a very high level
of protection for a general purpose microcontroller.
Both program and data E
In flash devices, this protection is removed by re-
programming the option. In this case, both pro-
gram and data E
erased, and the device can be reprogrammed.
Read-out protection selection depends on the de-
vice type:
– In Flash devices it is enabled and removed
– In ROM devices it is enabled by mask option
4.5.2 Flash Write/Erase Protection
Write/erase protection, when set, makes it impos-
sible to both overwrite and erase program memo-
ry. It does not apply to E
provide advanced security to applications and pre-
vent any change being made to the memory con-
tent.
Warning: Once set, Write/erase protection can
never be removed. A write-protected flash device
is no longer reprogrammable.
Table 3. FLASH Register Map and Reset Values
through the FMP_R bit in the option byte.
specified in the Option List.
Address
(Hex.)
002Fh
FCSR
Reset Value
Register
Label
2
memory are automatically
2
2
memory are protected.
data. Its purpose is to
7
0
6
0
5
0
Write/erase protection is enabled through the
FMP_W bit in the option byte.
4.6 Related Documentation
For details on Flash programming and ICC proto-
col, refer to the ST7 Flash Programming Refer-
ence Manual and to the ST7 ICC Protocol Refer-
ence Manual
4.7 Register Description
FLASH CONTROL/STATUS REGISTER (FCSR)
Read/Write
Reset Value: 000 0000 (00h)
1st RASS Key: 0101 0110 (56h)
2nd RASS Key: 1010 1110 (AEh)
Note: This register is reserved for programming
using ICP, IAP or other programming methods. It
controls the XFlash programming and erasing op-
erations.
When an EPB or another programming tool is
used (in socket or ICP mode), the RASS keys are
sent automatically.
7
0
4
0
0
.
3
0
0
0
ST7LITE0x, ST7LITESx
OPT
2
0
0
OPT
LAT
1
0
LAT
PGM
15/125
0
0
PGM
0
1