CC2640 ADC使用疑问
时间:10-02
整理:3721RD
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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?
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。
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!
你好:我也遇到了这个问题,请问你实现了吗?
参考下面代码:
/*! * @brief Specifies 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. * * @note The 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. * * @warning Even 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;