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Application Note
AN_289 FT51A Programming Guide
Version 1.0
Document Reference No.: FT_000962 Clearance No.: FTDI# 483
24
Copyright © 2015 Future Technology Devices International Limited
The security bits are categorised as write forward, as once a particular level has been set it is not
possible to go back to a lower security level.
If the
flash_mtp_mem
operation is used then Shadow RAM byte 0x3FFF must contain the
security requirements for the chip. The address 0x3FFF should be reserved for this purpose.
Do not modify the values stored at Shadow RAM addresses 0x3FF8, 0x3FF9 and 0x3FFA.
These contain factory programmed values.