SAM9N12 Datasheet, PDF (951/1137 Pages) ATMEL Corporation – The ARM926EJ-S based SAM9CN12 features the frequently requested combination of user...

SAM9N12/SAM9CN11/SAM9CN12
Figure 43-9. Receiver Block Diagram
SSC_CR.RXEN
SSC_SR.RXEN
SSC_CR.RXDIS
SSC_TCMR.START
SSC_RCMR.START _{SSC_RFMR.MSBF}
TXEN
RXEN
SSC_RFMR.DATNB
RX Start Start
RF
Selector
RF
Start
Selector
RX Start
RX Controller
RC0R
RD
Receive Shift Register
SSC_RCMR.STTDLY != 0
load SSC_RSHR
load SSC_RHR
SSC_RFMR.FSLEN
SSC_RFMR.DATLEN
RX Controller counter reached STTDLY
Receiver Clock
43.7.4 Start
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).
11063G–ATARM–09-Oct-12
951