Atmel SAM4S-XPLD Atmel ATSAM4S-XPLD ATSAM4S-XPLD Hoja De Datos

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SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

Lock bits can be read using the Get Lock Bit command (GLB). The n

th

 lock bit is active when the bit n of the bit mask is

set..

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..

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.

In order to erase the Flash, the user must perform the following:



Power-off the chip



Power-on the chip with TST = 0

1

Write handshaking

CMDE

GLB

2

Read handshaking

DATA

Lock Bit Mask Status

0 = Lock bit is cleared

1 = Lock bit is set

1

Write handshaking

CMDE

SGPB or CGPB 

2

Write handshaking

DATA

GP NVM bit pattern value

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

1

Write handshaking

CMDE

SSE

2

Write handshaking

DATA

0