Atmel ARM-Based Evaluation Kit AT91SAM9N12-EK AT91SAM9N12-EK Data Sheet

624

SAM9N12/SAM9CN11/SAM9CN12 [DATASHEET]

11063K–ATARM–05-Nov-13

SPI Enable

CSAAT ?

PS ?

1

0

0

1

1

NPCS = SPI_TDR(PCS)

NPCS = SPI_MR(PCS)

Delay DLYBS

Serializer = SPI_TDR(TD)

TDRE = 1

Data Transfer

SPI_RDR(RD) = Serializer

RDRF = 1

TDRE ?

NPCS = 0xF

Delay DLYBCS

Fixed

 peripheral

Variable 

peripheral

Delay DLYBCT

0

1

CSAAT ?

0

TDRE ?

1

0

PS ?

0

1

SPI_TDR(PCS)

= NPCS ?

no

yes

SPI_MR(PCS)

= NPCS ?

no

NPCS = 0xF

Delay DLYBCS

NPCS = SPI_TDR(PCS)

NPCS = 0xF

Delay DLYBCS

NPCS = SPI_MR(PCS),

                SPI_TDR(PCS) 

Fixed

 peripheral

Variable 

peripheral

- NPCS defines the current Chip Select
- CSAAT, DLYBS, DLYBCT refer to the fields of the 
  Chip Select Register corresponding to the Current Chip Select
- When NPCS is 0xF, CSAAT is 0.