Datasheet

497
SAM3X / SAM3A [DATASHEET]
Atmel-11057C-ATARM-SAM3X-SAM3A-Datasheet_23-Mar-15
• BAT: Byte Access Type
This field is used only if DBW defines a 16-bit data bus.
• 1: Byte write access type:
– Write operation is controlled using NCS, NWR0, NWR1.
–Read operation is controlled using NCS and NRD.
• 0: Byte select access type:
– Write operation is controlled using NCS, NWE, NBS0, NBS1.
–Read operation is controlled using NCS, NRD, NBS0, NBS1.
• DBW: Data Bus Width
• TDF_CYCLES: Data Float Time
This field gives the integer number of clock cycles required by the external device to release the data after the rising edge
of the read controlling signal. The SMC always provide one full cycle of bus turnaround after the TDF_CYCLES period. The
external bus cannot be used by another chip select during TDF_CYCLES + 1 cycles. From 0 up to 15 TDF_CYCLES can
be set.
• TDF_MODE: TDF Optimization
1: TDF optimization is enabled.
–The number of TDF wait states is optimized using the setup period of the next read/write access.
0:
TDF
optimization is disabled.
–The number of TDF wait states is inserted b efore the next access begins.
Value Name Description
0 BIT_8 8-bit bus
1 BIT_16 16-bit bus