ADC不准，非常不准，问题在哪里？

只看该作者 · 2019-12-17 17:15

本帖最后由 Q80351951 于 2019-12-17 17:18 编辑

ADC不准，非常不准，问题在哪里？
uint8_t Adc_test(void)
{
      stc_adc_cfg_t stcAdcCfg;
      stc_adc_norm_cfg_t stcAdcNormCfg;

      DDL_ZERO_STRUCT(stcAdcCfg);
      DDL_ZERO_STRUCT(stcAdcNormCfg);

      if (Ok != Clk_SetPeripheralGate(ClkPeripheralAdcBgr, TRUE))
      {
            return Error;
      }

      Adc_Enable();
      M0P_BGR->CR_f.BGR_EN = 0x1u; //BGR必须使能
      M0P_BGR->CR_f.TS_EN = 0x0u;

      SysTick_m26_delay(3);

      stcAdcCfg.enAdcOpMode = AdcNormalMode;                //单次采样模式
      stcAdcCfg.enAdcClkSel = AdcClkSysTDiv1;                //PCLK
      stcAdcCfg.enAdcSampTimeSel = AdcSampTime8Clk; //4个采样时钟
      stcAdcCfg.enAdcRefVolSel = RefVolSelInBgr2p5; //RefVolSelAVDD;//参考电压:内部2.5V(avdd>3V,SPS<=200kHz)  SPS速率 = ADC时钟 / (采样时钟 + 16CLK)
      stcAdcCfg.bAdcInBufEn = TRUE;                               //电压跟随器如果使能，SPS采样速率 <=200K
      stcAdcCfg.u32AdcRegHighThd = 0u;                         //比较阈值上门限
      stcAdcCfg.u32AdcRegLowThd = 0u;                               //比较阈值下门限
      stcAdcCfg.enAdcTrig0Sel = AdcTrigDisable;       //ADC转换自动触发设置
      stcAdcCfg.enAdcTrig1Sel = AdcTrigDisable;
      Adc_Init(&stcAdcCfg);

      stcAdcNormCfg.enAdcNormModeCh = AdcAVccDiV3Input; //通道0 P24
      stcAdcNormCfg.bAdcResultAccEn = FALSE;
      Adc_ConfigNormMode(&stcAdcCfg, &stcAdcNormCfg);

      while (1)
      {
            Adc_Start();
            while (FALSE != Adc_PollBusyState())
                     ;
            Adc_GetResult(&batt_voltage_data);
            Adc_ClrAccResult();

            batt_voltage = batt_voltage_data * 7500 / 4096; //电池电压
            Uart1_Send_str((uint8_t *)"\r\n电");
            Uart1_Send_str(uint16_to_5DEC(batt_voltage));
            Uart1_Send_str((uint8_t *)" 电da");
            Uart1_Send_str(uint16_to_5DEC(batt_voltage_data));

            SysTick_m26_delay(1000);
            Wdt_Feed(); //喂狗
      }
}