【NXP OKdo E1双核Cortex M33开发板】测评+ A/D数据采集

jinglixixi

OKdo E1开发板具有A/D数据转换器，ADC CH0A通道所使用的引脚为PIO0_23，通过它可以对模拟信号进行采集。
现实数据采集的程序如下：

1. #define DEMO_LPADC_BASE            ADC0
   
2. #define DEMO_LPADC_USER_CHANNEL   0U
   
3. #define DEMO_LPADC_USER_CMDID     1U
   
4. #define DEMO_LPADC_VREF_SOURCE     kLPADC_Reference VoltageAlt2
   
5. #define DEMO_LPADC_DO_OFFSET_CALIBRATION   false
   
6. #define DEMO_LPADC_OFFSET_VALUE_A  10U
   
7. #define DEMO_LPADC_OFFSET_VALUE_B  10U
   
8. 
   
9. int main(void)
   
10. {
    
11.     uint32_t U;
    
12.         lpadc_config_t mLpadcConfigStruct;
    
13.     lpadc_conv_trigger_config_t mLpadcTriggerConfigStruct;
    
14.     lpadc_conv_command_config_t mLpadcCommandConfigStruct;
    
15.     lpadc_conv_result_t mLpadcResultConfigStruct;
    
16.     /* attach 12 MHz clock to FLEXCOMM0 (debug console) */
    
17.     CLOCK_AttachClk(BOARD_DEBUG_UART_CLK_ATTACH);
    
18.     BOARD_InitPins();
    
19.     BOARD_BootClockFROHF96M();
    
20.     BOARD_InitDebugConsole();
    
21.     CLOCK_SetClkDiv(kCLOCK_DivAdcAsyncClk, 16U, true);
    
22.     CLOCK_AttachClk(kMAIN_CLK_to_ADC_CLK);
    
23.     /* Disable LDOGPADC power down */
    
24.     POWER_DisablePD(kPDRUNCFG_PD_LDOGPADC);
    
25.     SysTick_Config(SystemCoreClock / 1000U);
    
26.         app_oled_init();
    
27.         OLED_Init();
    
28.         OLED_Clear();
    
29.         OLED_ShowString(0,0,"OKDOE1 TEST",16);
    
30.         OLED_ShowString(0,2,"ADC & OLED",16);
    
31.         OLED_ShowString(0,5,"ADC=     .",16);
    
32.     LPADC_GetDefaultConfig(&mLpadcConfigStruct);
    
33.     mLpadcConfigStruct.enableAnalogPreliminary = true;
    
34.     mLpadcConfigStruct.referenceVoltageSource = kLPADC_Reference VoltageAlt2;
    
35. #if defined(FSL_FEATURE_LPADC_HAS_CTRL_CAL_AVGS) && FSL_FEATURE_LPADC_HAS_CTRL_CAL_AVGS
    
36.     mLpadcConfigStruct.conversionAverageMode = kLPADC_ConversionAverage128;
    
37. #endif /* FSL_FEATURE_LPADC_HAS_CTRL_CAL_AVGS */
    
38.     LPADC_Init(ADC0, &mLpadcConfigStruct);
    
39. #if defined(FSL_FEATURE_LPADC_HAS_CTRL_CALOFS) && FSL_FEATURE_LPADC_HAS_CTRL_CALOFS
    
40. #if defined(FSL_FEATURE_LPADC_HAS_OFSTRIM) && FSL_FEATURE_LPADC_HAS_OFSTRIM
    
41.     /* Request offset calibration. */
    
42.     LPADC_SetOffsetValue(ADC0, 10U, 10U);
    
43. #endif /* FSL_FEATURE_LPADC_HAS_OFSTRIM */
    
44.     /* Request gain calibration. */
    
45.     LPADC_DoAutoCalibration(ADC0);
    
46. #endif /* FSL_FEATURE_LPADC_HAS_CTRL_CALOFS */
    
47. #if (defined(FSL_FEATURE_LPADC_HAS_CFG_CALOFS) && FSL_FEATURE_LPADC_HAS_CFG_CALOFS)
    
48.     /* Do auto calibration. */
    
49.     LPADC_DoAutoCalibration(ADC0);
    
50. #endif /* FSL_FEATURE_LPADC_HAS_CFG_CALOFS */
    
51.     /* Set conversion CMD configuration. */
    
52.     LPADC_GetDefaultConvCommandConfig(&mLpadcCommandConfigStruct);
    
53.     mLpadcCommandConfigStruct.channelNumber =0U;
    
54.     LPADC_SetConvCommandConfig(ADC0, 1U, &mLpadcCommandConfigStruct);
    
55.     /* Set trigger configuration. */
    
56.     LPADC_GetDefaultConvTriggerConfig(&mLpadcTriggerConfigStruct);
    
57.     mLpadcTriggerConfigStruct.targetCommandId       = 1U;
    
58.     mLpadcTriggerConfigStruct.enableHardwareTrigger = false;
    
59.     LPADC_SetConvTriggerConfig(ADC0, 0U, &mLpadcTriggerConfigStruct);
    
60. #if defined(FSL_FEATURE_LPADC_HAS_CMDL_CSCALE) && FSL_FEATURE_LPADC_HAS_CMDL_CSCALE
    
61.     while (1)
    
62.     {
    
63.         LPADC_DoSoftwareTrigger(ADC0, 1U); /* 1U is trigger0 mask. */
    
64. #if (defined(FSL_FEATURE_LPADC_FIFO_COUNT) && (FSL_FEATURE_LPADC_FIFO_COUNT == 2U))
    
65.         while (!LPADC_GetConvResult(ADC0, &mLpadcResultConfigStruct, 0U))
    
66. #else
    
67.         while (!LPADC_GetConvResult(ADC0, &mLpadcResultConfigStruct))
    
68. #endif /* FSL_FEATURE_LPADC_FIFO_COUNT */
    
69.         {
    
70.         }
    
71.                         U=mLpadcResultConfigStruct.convValue >> 3U;
    
72.                                 OLED_ShowNum(40,5,U,5,16);
    
73.                                 SysTick_DelayTicks(1000U);
    
74.     }
    
75. }
    

复制代码

在程序编译下载后，其运行效果如图1所示。

图1 OLED屏显示效果

在使用串口的情况下，其执行效果如图所示。其中的零值，则为输入引脚接地时所测得的值。

图2 串口输出效果