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

 566

SAM4S [DATASHEET]

11100E–ATARM–24-Jul-13

The transmitter and receiver can both be programmed to start their operations when an event occurs, respectively in the
Transmit Start Selection (START) field of SSC_TCMR and in the Receive Start Selection (START) field of SSC_RCMR. 

Under the following conditions the start event is independently programmable:



Continuous. In this case, the transmission starts as soon as a word is written in SSC_THR and the reception starts 
as soon as the Receiver is enabled.



Synchronously with the transmitter/receiver 



On detection of a falling/rising edge on TF/RF



On detection of a low level/high level on TF/RF



On detection of a level change or an edge on TF/RF

A start can be programmed in the same manner on either side of the Transmit/Receive Clock Register (RCMR/TCMR).
Thus, the start could be on TF (Transmit) or RF (Receive).

Moreover, the Receiver can start when data is detected in the bit stream with the Compare Functions.

Detection on TF/RF input/output is done by the field FSOS of the Transmit/Receive Frame Mode Register
(TFMR/RFMR).

SSC_RFMR.MSBF

SSC_RFMR.DATNB

SSC_TCMR.START

SSC_RCMR.START

SSC_RHR

SSC_RSHR

SSC_RFMR.FSLEN

SSC_RFMR.DATLEN

RX Controller counter reached STTDLY

RX Controller

RD

SSC_CR.RXEN

SSC_CR.RXDIS

SSC_SR.RXEN

Receiver Clock

RF

TXEN

RX Start

RF

RXEN

RC0R

SSC_RCMR.STTDLY = 0

Receive Shift Register

Start

Selector

Start

Selector

RX Start

load

load