XMOS XK-AUDIO-316-MC-AB, Руководство по оборудованию

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xcore.ai Multichannel Audio Board 1v1 Hardware Manual
Board Net xCORE GPIO Port Description
X_DAC_D0 X1D39 P1P0 Serial data output 0 (I2S or TDM)
X_DAC_D1 X1D38 P1O0 Serial data output 1 (I2S or TDM)
X_DAC_D2 X1D37 P1N0 Serial data output 2 (I2S or TDM)
X_DAC_D3 X1D36 P1M0 Serial data output 3 (I2S or TDM)
DAC_MUTE_N X0D16 P4D0 Output to mute audio when low
LRCK X1D01 P1B0 Serial left/right frame clock
BCLK X1D10 P1C0 Bit clock for serial data transfer
MCLK_DAC See note NA Buffered global audio master clock
Figure 9:
Analog output
xCORE GPIO
8 Digital audio output
Optical and coaxial digital audio outputs are provided. Both of these outputs can support
transmission of audio data in IEC60958 consumer mode (S/PDIF) format. This format
allows transmission of two channels of audio data at up to 192kHz. Note the optical
transmitter used on the board can only support up to 96kHz in this mode.
Additionally the optical output can transmit data in the ADAT optical format. This format
allows transmission of eight channels of audio data at 48kHz. The S/MUX extension to
ADAT allows four channels at 96kHz or two channels at 192kHz.
In order to reduce clock jitter on these outputs, the data outputs from xcore.ai are re-
clocked using the global audio master clock to synchronise the data into the audio clock
domain. This is achieved using simple external D-type flip-flops.
Figure 10:
Digital audio
output
The signals are generated from two 1-bit ports on xcore.ai.
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