ATSAM3U-EK Atmel, ATSAM3U-EK Datasheet - Page 20

• Manufacturer Part Number: ATSAM3U-EK
• Description: KIT EVAL FOR AT91SAM3U CORTEX
• Manufacturer: Atmel
• Type: MCUr

Specifications of ATSAM3U-EK

• Contents: Board
• Processor To Be Evaluated: SAM3U
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• Operating Supply Voltage: 3 V
• Silicon Manufacturer: Atmel
• Core Architecture: ARM
• Core Sub-architecture: Cortex - M3
• Silicon Core Number: SAM3U4E
• Silicon Family Name: SAM3U
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT91SAM3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6478E–ATARM–30-Mar-11
Evaluation Kit Hardware
4-12
The SAM3U4E programmable clock output is used to generate the WM8731 master clock (MCLK). The
SAM3U4E ODT (On-Die Termination) feature guarantees a signal integrity on this clock line without the
need for external discrete components.
WM8731 pin 21 MODE is pulled down by default; this configures the device as a TWI device for internal
register access.
Pin15 CSB is pulled up, which sets its TWI address as 33 [0x0011011].
The WM8731 digital interface works in slave mode on the SAM3U4E Synchronous Serial Controller
(SSC) interface, which means that Codec digital audio bit clock and ADC/DAC left/right control clock are
to be generated by the SAM3U4E.
Figure 4-14. Codec Slave Mode
The WM8731 ADC and DAC have separated left/right control clocks to run at different rates.
The bit clock is shared; it can be the SSC transmitter clock (TK) or the receiver clock (RK). The default
setting on SAM3U-EK is TK and RK shorted together through R97/R99. Please note that trying different
ADC/DAC rates would mean different RK/TK rates; this default setting can be modified.
The 0-Ohm resistors R46/R47/R97/R99 have been implemented to offer a disconnection possibility
(freeing these dedicated PIO lines for other custom usage).
Note: The ADC and DAC can run at different rates
WM8731
CODEC
ADCLRC
DACLRC
ADCDAT
DACDAT
BCLK
BCLK
PA31
PA30
PA27
PA26
SAM3U-EK Evaluation Kit User Guide
SAM3U4E