STEVAL-ISQ002V1 STMicroelectronics, STEVAL-ISQ002V1 Datasheet - Page 16

• Manufacturer Part Number: STEVAL-ISQ002V1
• Description: BOARD EVAL BASED ON ST72264G1
• Manufacturer: STMicroelectronics

Specifications of STEVAL-ISQ002V1

• Main Purpose: Interface, PMBus
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ST72F264
• Primary Attributes: The PMBus™ Interface Using the ST7 I2C Peripheral
• Secondary Attributes: Firmware in C Language
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6423

ST72260Gx, ST72262Gx, ST72264Gx
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
Read-out protection, when selected, provides a
protection against Program Memory content ex-
traction and against write access to Flash memo-
ry. Even if no protection can be considered as to-
tally unbreakable, the feature provides a very high
level of protection for a general purpose microcon-
troller.
In flash devices, this protection is removed by re-
programming the option. In this case the program
memory is automatically 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. Its purpose is to provide advanced security to
applications and prevent any change being made
to the memory content.
Warning: Once set, Write/erase protection can
never be removed. A write-protected flash device
is no longer reprogrammable.
Write/erase protection is enabled through the
FMP_W bit in the option byte.
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through the FMP_R bit in the option byte.
specified in the Option List.
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
AN1477: Emulated data EEPROM with XFlash
memory
AN1576: IAP drivers for ST7 HDFlash or XFlash
MCUs
AN1575: On Board Programming methods for ST7
HDFlash or XFlash MCUs
AN1070: Checksum self checking capability
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
0
.
0
0
0
OPT
LAT
PGM
0