Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK データシート

 602

SAM9M10 [DATASHEET]

6355F–ATARM–12-Mar-13

– Master Clock divided by 3 if Receiver Frame Synchro is output

In addition, the maximum clock speed allowed on the TK pin is:

– Master Clock divided by 6 if Transmit Frame Synchro is input

– Master Clock divided by 2 if Transmit Frame Synchro is output

A transmitted frame is triggered by a start event and can be followed by synchronization data before data
transmission.

The start event is configured by setting the Transmit Clock Mode Register (SSC_TCMR). 

The frame synchronization is configured setting the Transmit Frame Mode Register (SSC_TFMR). 

To transmit data, the transmitter uses a shift register clocked by the transmitter clock signal and the start mode
selected in the SSC_TCMR. Data is written by the application to the SSC_THR register then transferred to the shift
register according to the data format selected.

When both the SSC_THR and the transmit shift register are empty, the status flag TXEMPTY is set in SSC_SR.
When the Transmit Holding register is transferred in the Transmit shift register, the status flag TXRDY is set in
SSC_SR and additional data can be loaded in the holding register.

Transmitter Block Diagram

A received frame is triggered by a start event and can be followed by synchronization data before data
transmission.

The start event is configured setting the Receive Clock Mode Register (SSC_RCMR). 

The frame synchronization is configured setting the Receive Frame Mode Register (SSC_RFMR). 

Transmit Shift Register

TD

SSC_TFMR.FSLEN

SSC_TFMR.DATLEN

SSC_TCMR.STTDLY
SSC_TFMR.FSDEN
SSC_TFMR.DATNB
SSC_TFMR.DATDEF
SSC_TFMR.MSBF

SSC_TCMR.STTDLY != 0

SSC_TFMR.FSDEN

1

0

TX Controller

SSC_TCMR.START

RF

Start

Selector

TXEN

RX Start

TXEN

RF

Start

Selector

RXEN

RC0R

TX Start

TX Start

Transmitter Clock

TX Controller counter reached STTDLY

SSC_RCMR.START

SSC_THR

SSC_TSHR

SSC_CRTXEN

SSC_SRTXEN

SSC_CRTXDIS