Analog Devices ADSP-TS201S EZ-KIT Lite, Руководство пользователя

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Audio Interface
1-12 ADSP-TS201S EZ-KIT Lite Evaluation System Manual
Audio Interface
The audio interface of the EZ-KIT Lite board allows you to interface with
the board’s analog-to-digital converter (ADC) and digital-to-analog con-
verter (DAC). The audio interface consists of two main ICs: AD1871 and
AD1854.
The AD1871 is a stereo audio ADC intended for digital audio applica-
tions requiring high-performance analog-to-digital conversion. The
AD1871 provides 97 dB THD+N and 107 dB dynamic range.
The AD1854 is a high-performance, single-chip stereo, audio DAC deliv-
ering 113 dB dynamic range and 112 dB SNR at a 48 kHz sample rate.
Because the ADSP-TS201S processor does not have any SPORTs, a Xilinx
complex programmable logic device (CPLD) generates the audio interface
control signals between the processor and the audio circuit. Setting the
FLAG3
signal of processor A high enables the audio interface inside of the
CPLD. Once the audio interface has been enabled, the audio data can be
transferred to and from the processor by generating a
DMAR0
cycle. The
audio data interfaces with the processor via the lowest 24 bits of the data
bus (
D23–0
).
A CPLD IO connector (
P6
) has been added to allow a user to connect to
the CPLD and the external port of the ADSP-TS201S (DSP A) processor.
Refer to the schematic for information on how the connector is wired to
the CPLD. Refer to the audio example program included in the EZ-KIT
Lite’s installation directory for more information on how to use the audio
interface. Refer to
“Audio (J9 and J10)” on page 2-21 for information
about the audio connectors.