Atmel Xplained Pro Evaluation Kit ATSAM4E-XPRO ATSAM4E-XPRO Data Sheet
Product codes
ATSAM4E-XPRO
537
SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
Figure 28-11. WRITE_MODE = 1. The write operation is controlled by NWE
28.8.4.2 Write is Controlled by NCS (WRITE_MODE = 0)
shows the waveforms of a write operation with WRITE_MODE set to 0. The data is put on the bus
during the pulse and hold steps of the NCS signal. The internal data buffers are switched to output mode after the
NCS_WR_SETUP time, and until the end of the write cycle, regardless of the programmed waveform on NWE.
NCS_WR_SETUP time, and until the end of the write cycle, regardless of the programmed waveform on NWE.
Figure 28-12. WRITE_MODE = 0. The write operation is controlled by NCS
28.8.5 Write Protected Registers
To prevent any single software error that may corrupt SMC behavior, the registers listed below can be write-
protected by setting the WPEN bit in the SMC Write Protect Mode Register (SMC_WPMR).
protected by setting the WPEN bit in the SMC Write Protect Mode Register (SMC_WPMR).
If a write access in a write-protected register is detected, then the WPVS flag in the SMC Write Protect Status
Register (SMC_WPSR) is set and the field WPVSRC indicates in which register the write access has been
attempted.
Register (SMC_WPSR) is set and the field WPVSRC indicates in which register the write access has been
attempted.
The WPVS flag is automatically reset after reading the SMC Write Protect Status Register (SMC_WPSR).
List of the write-protected registers:
MCK
D[7:0]
NCS
A[23:0]
NWE
MCK
D[7:0]
NCS
NWE
A[23:0]