Texas Instruments PurePath TAS5766M, Руководство пользователя

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40 PurePath™ Smart Amp User Manual (TAS5766M/68M)
6.4 Integrating the Output Header File into the End-System
The PurePath™ Console 3 User Manual [ 7 ] provides detailed information an example code on
how to parse a header file in the Appendix sections.
The general concept is simple. The header file obtained from Section 6.3 contains an array of
two element structures in which the first member is the register address (or offset) and the
second member is the data written to that register. To distinguish between an actual register
write and special commands in the parser, the
cfg_reg is defined as a union, as shown in Figure
16 . The parser would interpret a value of 128 and above as a command, rather than an offset.
This does not cause any conflicts with target devices because none have registers above
Register 127.
// Definition of the cfg_reg type
typedef union
{
struct
{
cfg_u8 offset;
cfg_u8 value;
};
struct
{
cfg_u8 command;
cfg_u8 param;
};
} cfg_reg;
Figure 16. Example Header File Output Snippet
The microcontroller would simply need to parse an array similar to the one shown in Figure 15
and generate I
2
C commands.
6.5 Smart Amp Verification in the End-System
Once the Smart Amp code (header file) is implemented in the end-system, basic verification can
begin.
Basic Verification:
1. Ensure power supplies for Smart Amp are proper.
2. Ensure audio clocks are present. Depending on the configuration (as defined by the .ddf
file used to generate the header file) audio clocks may be generated by the Smart Amp
device or may be input from an external source.
3. Ensure the word clock frequency matches the sample rate of the Smart Amp plug-in by
measuring with an oscilloscope or multi-meter.
4. Set the volume of the host processor to a low level (e.g. -20dB to -40dB).
5. Unmute the Smart Amp device. For example, set the XSMT pin of the TAS5766M high.
6. Play a music file.