Datasheet

353
6120F–ATARM–03-Oct-06
AT91SAM7X512/256/128 Preliminary
31.6.6.1 Compare Functions
Compare 0 can be one start event of the Receiver. In this case, the receiver compares at each
new sample the last FSLEN bits received at the FSLEN lower bit of the data contained in the
Compare 0 Register (SSC_RC0R). When this start event is selected, the user can program
the Receiver to start a new data transfer either by writing a new Compare 0, or by receiving
continuously until Compare 1 occurs. This selection is done with the bit (STOP) in
SSC_RCMR.
31.6.7 Data Format
The data framing format of both the transmitter and the receiver are programmable through
the Transmitter Frame Mode Register (SSC_TFMR) and the Receiver Frame Mode Register
(SSC_RFMR). In either case, the user can independently select:
• the event that starts the data transfer (START)
• the delay in number of bit periods between the start event and the first data bit (
STTDLY)
• the length of the data (DATLEN)
• the number of data to be transferred for each start event (DATNB).
• the length of synchronization transferred for each start event (FSLEN)
• the bit sense: most or lowest significant bit first (MSBF).
Additionally, the transmitter can be used to transfer synchronization and select the level driven
on the TD pin while not in data transfer operation. This is done respectively by the Frame Sync
Data Enable (FSDEN) and by the Data Default Value (DATDEF) bits in SSC_TFMR.