Usb Connector And Transceiver [19 & I]; Audio Codec [C] - XMOS XS1-L2 Hardware Manual

USB Audio 2.0 Reference Design, XS1-L2 Edition Hardware Manual (1.6)
The MODE4 pin is held low on the board. This causes the second XCore to boot from
a link connected to first XCore, rather than its own SPI FLASH.
4 USB Connector and Transceiver [19 & I]
The board uses a standard USB series B receptacle for USB connectivity.
The high-speed USB signals are connected to an SMSC® USB3318 USB transceiver
which provides a ULPI connection to XCore 0 of the XS1-L2.
On power-up, a pulldown resistor holds the transceiver in reset until the XS1-L2 is
ready to begin USB activity. The USB transceiver reset pin is connected to port X0P1M
of the XS1-L2 in order that it can be controlled by software.
The transceiver uses the 13MHz clock provided by a discrete oscillator which doubles
as the reference clock for the XS1-L2.

5 Audio CODEC [C]

The board is equiped with a 24 bit, 192kHz multi-channel audio CODEC (Cirrus
Logic® CS42448).
The CODEC is configured via an I
0x48.
The CODEC can be configured to provide audio clocks (master mode) or with all
clocks being inputs (slave mode).
The CODEC has seperate LRCLK and SCLK I/Os for ADC and DAC. These are both
connected to a single I/O pin on the XCore. Clock buffers are provided for SCLK and
LRCLK I/Os to remove any potential contention issues.
The control pin (CODEC_MODE) for the buffers is mapped to bit 1 of port X1P4A on
the XS1-L2.
When using the codec in slave mode the clocks should be connected together.
The CODEC has three internal modes depending on the sampling rate used. These
change the oversampling ratio used internally in the CODEC. The three modes are
shown below:
Downloaded from Elcodis.com electronic components distributor
2
C serial configuration interface with slave address
CODEC_MODE Clock Mode
0 Clocks Connected
1 Clocks Disconnected
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