SAM3N0B Atmel Corporation, SAM3N0B Datasheet - Page 301

• Manufacturer Part Number: SAM3N0B
• Manufacturer: Atmel Corporation

19.2.5.6
19.2.5.7
11011A–ATARM–04-Oct-10
Flash Security Bit Command
Memory Write 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.
Table 19-15. Set Security Bit Command
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.
In order to erase the Flash, the user must perform the following:
Then it is possible to return to FFPI mode and check that Flash is erased.
This command is used to perform a write access to any memory location.
The Memory Write command (WRAM) is optimized for consecutive writes. Write handshaking
can be chained; an internal address buffer is automatically increased.
Table 19-16. Write Command
Step
1
2
Step
1
2
3
4
5
...
n
n+1
n+2
n+3
...
• Power-off the chip
• Power-on the chip with TST = 0
• Assert Erase during a period of more than 220 ms
• Power-off the chip
Handshake Sequence
Write handshaking
Write handshaking
Handshake Sequence
Write handshaking
Write handshaking
Write handshaking
Write handshaking
Write handshaking
...
Write handshaking
Write handshaking
Write handshaking
Write handshaking
...
MODE[3:0]
CMDE
ADDR0
ADDR1
DATA
DATA
...
ADDR0
ADDR1
DATA
DATA
...
MODE[3:0]
CMDE
DATA
DATA[15:0]
WRAM
Memory Address LSB
Memory Address
*Memory Address++
*Memory Address++
...
Memory Address LSB
Memory Address
*Memory Address++
*Memory Address++
...
DATA[15:0] or DATA[7:0]
SSE
0
SAM3N
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