at32uc3b0512-z2ues ATMEL Corporation, at32uc3b0512-z2ues Datasheet - Page 268

• Manufacturer Part Number: at32uc3b0512-z2ues
• Description: 32-bit Avr Microcontroller
• Manufacturer: ATMEL Corporation

20.7.1.4
20.7.2
32059J–12/2010
Transmitter Operations
Serial clock ratio considerations
Figure 20-7. Receiver Clock Management
The transmitter and the receiver can be programmed to operate with the clock signals provided
on either the TX_CLOCK or RX_CLOCK pins. This allows the SSC to support many slave-mode
data transfers. In this case, the maximum clock speed allowed on the RX_CLOCK pin is:
In addition, the maximum clock speed allowed on the TX_CLOCK pin is:
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 writing to the TCMR register. See
The frame synchronization is configured by writing to the Transmit Frame Mode Register
(TFMR). See
To transmit data, the transmitter uses a shift register clocked by the transmitter clock signal and
the start mode selected in the TCMR register. Data is written by the user to the Transmit Holding
Register (THR) then transferred to the shift register according to the data format selected.
When both the THR and the transmit shift registers are empty, the Transmit Empty bit is set in
the Status Register (SR.TXEMPTY). When the THR register is transferred in the transmit shift
register, the Transmit Ready bit is set in the SR register (SR.TXREADY) and additional data can
be loaded in the THR register.
Transmitter
Divider
RX_CLOCK
Clock
Clock
– CLK_SSC divided by two if RX_FRAME_SYNC is input.
– CLK_SSC divided by three if RX_FRAME_SYNC is output.
– CLK_SSC divided by six if TX_FRAME_SYNC is input.
– CLK_SSC divided by two if TX_FRAME_SYNC is output.
Section
20.7.5.
MUX
CKS
CKO
Controller
Tri-state
MUX
INV
CKI
Data Transfer
Section
Controller
Tri-state
CKG
20.7.4.
AT32UC3B
Receiver
Output
Clock
Clock
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