68 lines
2.8 KiB
ReStructuredText
68 lines
2.8 KiB
ReStructuredText
.. |I2S| replace:: I\ :sup:`2`\ S
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I2S/TDM Library
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===============
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:Version: 5.1.0
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:Vendor: XMOS
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Summary
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-------
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A software library that allows you to control an |I2S| or TDM (time
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division multiplexed) bus via xCORE ports. |I2S| and TDM are digital
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data streaming interfaces particularly appropriate for transmission of
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audio data. The components in the library
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are controlled via C using the XMOS multicore extensions (xC) and
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can either act as |I2S| master, TDM master or |I2S| slave.
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Features
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........
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* |I2S| master, TDM master and |I2S| slave modes.
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* Handles multiple input and output data lines.
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* Support for standard |I2S|, left justified or right justified
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data modes for |I2S|.
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* Support for multiple formats of TDM synchronization signal.
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* Efficient "frame-based" versions of |I2S| master and slave allowing use of processor cycles in between I2S signal handling.
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* Sample rate support up to 192kHz or 768kHz for "frame-based" versions.
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* Up to 32 channels in/32 channels out (depending on sample rate and protocol).
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Resource Usage
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..............
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The I2S and TDM modules use one logical core and between 1.6 and 2.1kB of memory. IO usage is 1 x 1b port for each signal.
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Software version and dependencies
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.................................
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The CHANGELOG contains information about the current and previous versions.
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For a list of direct dependencies, look for DEPENDENT_MODULES in lib_i2s/module_build_info.
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Notes on "frame-based" |I2S| implementations
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............................................
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The library supports both "sample-based" and "frame-based" versions of |I2S| master and slave. The "frame-based" versions are recommended for new designs and support higher |I2S| channel counts and rates. In addition, the number of callbacks to pass data to and from the |I2S| handler task are reduced. "Frame-based" |I2S| pass an array of channels per sample period whereas "sample-based" versions make a callback per channel within a sample period. The "frame-based" callbacks are all grouped together allowing the user side to make maximum use of the MIPS between |I2S| frames. For example, a 48kHz (20.83us) |I2S| interface supports a total of 19us processing per sample period, in any order, across the callbacks. The older "sample-based" versions are currently maintained to provide compatibility with existing code examples.
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Related application notes
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.........................
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The following application notes use this library:
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* AN00162 - Using the |I2S| library
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Required Software (dependencies)
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================================
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* lib_xassert (www.github.com/xmos/lib_xassert)
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Documentation
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=============
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You can find the documentation for this software in the /doc directory of the package.
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Support
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=======
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This package is supported by XMOS Ltd. Issues can be raised against the software at: http://www.xmos.com/support
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