AT91SAM9R64_1 Datasheet, PDF (502/903 Pages) ATMEL Corporation – AT91 ARM Thumb Microcontrollers

(CKS field) and at the same time Continuous Transmit Clock (CKO field) might lead to unpredict-
able results.
Figure 35-6. Transmitter Clock Management
TK (pin)
Receiver
Clock
MUX
Tri_state
Controller
Clock
Output
Divider
Clock
CKO
Data Transfer
CKS
INV
MUX
Tri-state
Controller
Transmitter
Clock
CKI
CKG
35.6.1.3
Receiver Clock Management
The receiver clock is generated from the transmitter clock or the divider clock or an external
clock scanned on the RK I/O pad. The Receive Clock is selected by the CKS field in
SSC_RCMR (Receive Clock Mode Register). Receive Clocks can be inverted independently by
the CKI bits in SSC_RCMR.
The receiver can also drive the RK I/O pad continuously or be limited to the actual data transfer.
The clock output is configured by the SSC_RCMR register. The Receive Clock Inversion (CKI)
bits have no effect on the clock outputs. Programming the RCMR register to select RK pin (CKS
field) and at the same time Continuous Receive Clock (CKO field) can lead to unpredictable
results.
Figure 35-7. Receiver Clock Management
RK (pin)
Transmitter
Clock
MUX
Tri-state
Controller
Clock
Output
Divider
Clock
CKO
Data Transfer
CKS
INV
MUX
Tri-state
Controller
Receiver
Clock
CKI
CKG
502 AT91SAM9R64/RL64 Preliminary
6289C–ATARM–28-May-09