# MIC_StartAutoSampling

## Syntax

  `#include <nitro/spi.h>`

      MICResult MIC_StartAutoSampling(
                  const MICAutoParam*    param );

## Arguments

param | Specifies a pointer to a `MICAutoParam`-type auto-sampling settings structure.

## Return Values

Returns the processing result as a `MICResult` enumerated type. Returns `MIC_RESULT_SUCCESS` if processing completes successfully, and some other value if the process fails for some reason.

## Description

Starts microphone auto-sampling. This function issues a request to the ARM7 processor to start auto-sampling, waits for ARM7 to respond, and returns the process result. This is a synchronous version of the `MIC_StartAutoSamplingAsync` function. Where the input volume exceeds the minimum or maximum value, the output data will be clamped. It is possible to use the `PM_SetAmpGain*` functions to adjust the input volume that can be sampled.

This function will return `MIC_RESULT_INVALID_COMMAND` when the CODEC is running in CODEC-TWL mode, because auto-sampling cannot be run at an arbitrary frequency in CODEC-TWL mode.

## Note

This function waits for a PXI interrupt for synchronization purposes. Do not call it when PXI interrupts are prohibited.
It is possible to operate other ARM7 processor peripherals (SPI device) during microphone auto-sampling. However, note that if another SPI device had taken over the access for a long time, the microphone would keep returning a certain value during that time.

## See Also

`MIC_StartAutoSampling`, `MIC_StopAutoSampling`, `MIC_AdjustAutoSampling`, `PM_SetAmpGain`

## Revision History

2008/01/09 Revised a description of differences in behavior due to the CODEC mode.
2007/11/07 Added a description of operations on the TWL platform.
2005/03/08 Standardized Japanese terminology for "interrupt."
2005/01/11 Revised Return Values and Description, and added functions to See Also.
2004/09/17 Changed the type of the `param` argument.
2004/08/10 Added explanations related to input volume, and touch panel sampling during microphone auto-sampling.
2004/06/01 Initial version.

CONFIDENTIAL