Atmel Evaluation Kit for the SAM4E Series of Flash Microcontrollers ATSAM4E-EK ATSAM4E-EK Data Sheet

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SAM4E [DATASHEET]

Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14

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



Assert Erase during a period of more than 220 ms



Power-off the chip

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. 

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