Atmel SAM4S-XPLD Atmel ATSAM4S-XPLD ATSAM4S-XPLD Fiche De Données

 616

SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

0 = Local loopback path disabled. 

1 = Local loopback path enabled 

LLB controls the local loopback on the data serializer for testing in Master Mode only. (MISO is internally connected on MOSI.)

This field is only used if Fixed Peripheral Select is active (PS = 0).

If PCSDEC = 0: 

PCS = xxx0

NPCS[3:0] = 1110

PCS = xx01

NPCS[3:0] = 1101     

PCS = x011

NPCS[3:0] = 1011

PCS = 0111

NPCS[3:0] = 0111

PCS = 1111

forbidden (no peripheral is selected)

(x = don’t care)

If PCSDEC = 1:

NPCS[3:0] output signals = PCS.

This field defines the delay from NPCS inactive to the activation of another NPCS. The DLYBCS time guarantees non-overlap-
ping chip selects and solves bus contentions in case of peripherals having long data float times.

If DLYBCS is less than or equal to six, six MCK periods will be inserted by default.

Otherwise, the following equation determines the delay:

Delay Between Chip Selects

-----------------------

=