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

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SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

Each part contains a User Signature of 512-bytes. It can be used by the user for storage. Read, write and erase of this
area is allowed.

To read the User Signature, the sequence is as follows:



Send the Start Read User Signature command (STUS) by writing the Flash Command Register with the STUS 
command.



When the User Signature is ready to be read, the FRDY bit in the Flash Programming Status Register 
(EEFC_FSR) falls.



The User Signature is located in the first 512 bytes of the Flash memory mapping, thus, at the address 
0x00400000-0x004001FF.



To stop the User Signature mode, the user needs to send the Stop Read User Signature command (SPUS) by 
writing the Flash Command Register with the SPUS command.



When the Stop Read User Signature command (SPUI) has been performed, the FRDY bit in the Flash 
Programming Status Register (EEFC_FSR) rises. If an interrupt was enabled by setting the FRDY bit in 
EEFC_FMR, the interrupt line of the NVIC is activated.

Note that during the sequence, the software can not run out of Flash (or the second plane, in case of dual plane).

One error can be detected in the EEFC_FSR register after this sequence: 



Command Error: a bad keyword has been written in the EEFC_FCR register.

To write the User Signature, the sequence is:



Write the full page, at any page address, within the internal memory area address space.



Send the Write User Signature command (WUS) by writing the Flash Command Register with the WUS command.



When programming is completed, the FRDY bit in the Flash Programming Status Register (EEFC_FSR) rises. If 
an interrupt has been enabled by setting the FRDY bit in EEFC_FMR, the corresponding interrupt line of the NVIC 
is activated.

Two errors can be detected in the EEFC_FSR register after this sequence: 



Command Error: a bad keyword has been written in the EEFC_FCR register.



Flash Error: at the end of the programming, the WriteVerify test of the Flash memory has failed.

To erase the User Signature, the sequence is:



Send the Erase User Signature command (EUS) by writing the Flash Command Register with the EUS command.



When programming is completed, the FRDY bit in the Flash Programming Status Register (EEFC_FSR) rises. If 
an interrupt has been enabled by setting the FRDY bit in EEFC_FMR, the corresponding interrupt line of the NVIC 
is activated.

Two errors can be detected in the EEFC_FSR register after this sequence: 



Command Error: a bad keyword has been written in the EEFC_FCR register.



Flash Error: at the end of the programming, the EraseVerify test of the Flash memory has failed.