USBB17AP77016-XXX-B11 NEC Electronics, USBB17AP77016-XXX-B11 Datasheet - Page 22

• Manufacturer Part Number: USBB17AP77016-XXX-B11
• Description: DSP middleware(WMA (Windows Media Audio)decoder)
• Manufacturer: NEC Electronics

2.3.6
22
[Classification]
[Function name]
[Summary of function] Supplements the input buffer with the bit stream data required for decoding.
[Format]
[Arguments]
[Return value]
[Function]
[Usable registers]
[Usable hardware resources]
[Remark]
wmad_FileCBGetData function (user-defined function)
When using the repeat instruction in this function, the interrupt servicing may be delayed if
Input data acquisition function
wmad_FileCBGetData
The wmad_FileDecodeInit and wmad_FileDecodeData functions call this function in call
DP0 format.
This function is called from the wmad_FileDecodeInit and wmad_FileDecodeData
functions a number of times each to supplement the input buffer with the bit stream data
required for WMA decoding.
Set the start address of this function using the wmad_FileDecodeInit function.
R0, R1, R2, R3, R4, R5, DP0, DP1
Caution When using registers other than the above, be sure to save their contents
the number of repetitions is large. Similarly, if the number of execution cycles of this
function is large, decoding may not be able to be performed in real time. Also, be sure to
set the stack level of this function so that the total stack level of the wmad_FileCBGetData
function, wmad_FileDecodeData function, and other functions used by the user does not
exceed 15.
R0
R1
R0
R2L
Stack level
Loop stack level
Return Value
Argument
to memory before use.
CHAPTER 2 LIBRARY SPECIFICATIONS
User’s Manual U15683EJ1V0UM
Size of requested data [bytes]
Offset from start of bit stream data [bytes]
Size of acquired data [bytes]
Start address of input buffer
Description
Description
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