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SAM4CP [DATASHEET]
43051E–ATPL–08/14
In the same way, the
Clear Lock
command
(CLB)
is used to clear lock bits.
Lock bits can be read using Get Lock Bit command (GLB). The n
th
lock bit is active when the bit n of the bit mask is set.
23.3.5.5 Flash General-purpose NVM Commands
General-purpose NVM bits (GP NVM bits) can be set using the Set GPNVM command (SGPB). This command also
activates GP NVM bits. A bit mask is provided as argument to the command. When bit 0 of the bit mask is set, then the
first GP NVM bit is activated.
In the same way, the Clear GPNVM command (CGPB) is used to clear general-purpose NVM bits. The general-purpose
NVM bit is deactivated when the corresponding bit in the pattern value is set to 1.
General-purpose NVM bits can be read using the
Get GPNVM Bit
command
(GGPB)
. The n
th
GP NVM bit is active when
bit n of the bit mask is set.
23.3.5.6 Flash Security Bit Command
A security bit can be set using the Set Security Bit command (SSE). Once the security bit is active, the Fast Flash
programming is disabled. No other command can be run. An event on the Erase pin can erase the security bit once the
contents of the Flash have been erased.
Once the security bit is set, it is not possible to access FFPI. The only way to erase the security bit is to erase the Flash.
Table 23-9.
Set and Clear Lock Bit Command
Step
Handshake Sequence
MODE[3:0]
DATA[15:0]
1
Write handshaking
CMDE
SLB or CLB
2
Write handshaking
DATA
Bit Mask
Table 23-10. Get Lock Bit Command
Step
Handshake Sequence
MODE[3:0]
DATA[15:0]
1
Write handshaking
CMDE
GLB
2
Read handshaking
DATA
Lock Bit Mask Status
0 = Lock bit is cleared
1 = Lock bit is set
Table 23-11. Set/Clear GP NVM Command
Step
Handshake Sequence
MODE[3:0]
DATA[15:0]
1
Write handshaking
CMDE
SGPB or CGPB
2
Write handshaking
DATA
GP NVM bit pattern value
Table 23-12. Get GP NVM Bit Command
Step
Handshake Sequence
MODE[3:0]
DATA[15:0]
1
Write handshaking
CMDE
GGPB
2
Read handshaking
DATA
GP NVM Bit Mask Status
0 = GP NVM bit is cleared
1 = GP NVM bit is set
Table 23-13. Set Security Bit Command
Step
Handshake Sequence
MODE[3:0]
DATA[15:0]
1
Write handshaking
CMDE
SSE
2
Write handshaking
DATA
0