CC2640 ADC使用疑问

现在需要使用CC2640的ADC采集一个音频信号，要求采样率为22050Hz。

现在可以采集回数据，但是如何设置采样率？

看了芯片手册、驱动API都没有发现哪里有这个设置。

请大婶们指点一下，哪里有这方面的说明？

Yan：

xianbin,

去下载最新的TRM： http://www.ti.com/lit/ug/swcu117d/swcu117d.pdf

里面的17.4.8.8 章会告诉你哪里去设置寄存器。

Renjun zhengjun：

回复 Yan:

您好，请问一下，因项目的需要，我需要在CC2640  ADC输入前端做一个跟随电路，请推荐一下合适的运放，CC2640这边的话关于ADC的资料较少！

xianglin dong：

你好：我也遇到了这个问题，请问你实现了吗？

Rex Kung：

参考下面代码：

/*!*@briefSpecifies whether the internal reference of the ADC is sourced from the battery voltage or a fixed internal source.**- In practice, using the internal fixed voltage reference sets the upper range of the ADC to a fixed value. That value is 4.3V with*input scaling enabled and ~1.4785V with input scaling disabled. In this mode, the output is a function of the input voltage multiplied*by the resolution in alternatives (not bits) divided by the upper voltage range of the ADC. Output = Input (V) * 2^12 / (ADC range (V))**- Using VDDS as a reference scales the upper range of the ADC with the battery voltage. As the battery depletes and its voltage drops, so does*the range of the ADC. This is helpful when measuring signals that are generated relative to the battery voltage. In this mode, the output is*a function of the input voltage multiplied by the resolution in alternatives (not bits) divided by VDDS multiplied by a scaling factor derived*from the input scaling. Output = Input (V) * 2^12 / (VDDS (V) * Scaling factor), where the scaling factor is ~1.4785/4.3 for input scaling*disabled and 1 for input scaling enabled.**@noteThe actual reference values are slightly different for each device and are higher than the values specified above. This gain is saved in*the FCFG. The function ::ADC_convertRawToMicroVolts() must be used to derive actual voltage values. Do not attempt to compare raw values*between devices or derive a voltage from them yourself. The results of doing so will only be approximately correct.**@warningEven though the upper voltage range of the ADC is 4.3 volts in fixed mode with input scaling enabled, the input should never exceed*VDDS as per the data sheet.*/
typedef enum ADCCC26XX_Reference_Source {ADCCC26XX_FIXED_REFERENCE= AUXADC_REF_FIXED,ADCCC26XX_VDDS_REFERENCE= AUXADC_REF_VDDS_REL
} ADCCC26XX_Reference_Source;