Other Parts Discussed in Thread: LAUNCHXL-F280049C,
使用官方的LAUNCHXL-F280049C开发板,跑adc_ex1_soc_software例程验证ADC采样的问题顶,我在while(1)循环中把最后的ESTOP0屏蔽,然后在线调试,观察myADC0Result0的数值变化,给开发板的A0通道接入了信号源,给1V,发现转换结果在1200-1300之间跳变,数据很不准确,想问下是什么原因?
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使用官方的LAUNCHXL-F280049C开发板,跑adc_ex1_soc_software例程验证ADC采样的问题顶,我在while(1)循环中把最后的ESTOP0屏蔽,然后在线调试,观察myADC0Result0的数值变化,给开发板的A0通道接入了信号源,给1V,发现转换结果在1200-1300之间跳变,数据很不准确,想问下是什么原因?
//#############################################################################
//
// FILE: adc_ex1_soc_software.c
//
// TITLE: ADC Software Triggering
//
//! \addtogroup driver_example_list
//! <h1>ADC Software Triggering</h1>
//!
//! This example converts some voltages on ADCA and ADCC based on a software
//! trigger.
//!
//! The ADCC will not convert until ADCA is complete, so the ADCs will not run
//! asynchronously. However, this is much less efficient than allowing the ADCs
//! to convert synchronously in parallel (for example, by using an ePWM
//! trigger).
//!
//! \b External \b Connections \n
//! - A0, A1, C2, and C3 should be connected to signals to convert
//!
//! \b Watch \b Variables \n
//! - \b myADC0Result0 - Digital representation of the voltage on pin A0
//! - \b myADC0Result1 - Digital representation of the voltage on pin A1
//! - \b myADC1Result0 - Digital representation of the voltage on pin C2
//! - \b myADC1Result1 - Digital representation of the voltage on pin C3
//!
//
//#############################################################################
//
//
// $Copyright:
// Copyright (C) 2024 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the
// distribution.
//
// Neither the name of Texas Instruments Incorporated nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//#############################################################################
//
//
// Included Files
//
#include "driverlib.h"
#include "device.h"
#include "board.h"
//
// Globals
//
uint16_t myADC0Result0;
uint16_t myADC0Result1;
uint16_t myADC1Result0;
uint16_t myADC1Result1;
//
// Main
//
void main(void)
{
//
// Initialize device clock and peripherals
//
Device_init();
//
// Disable pin locks and enable internal pullups.
//
Device_initGPIO();
//
// Initialize PIE and clear PIE registers. Disables CPU interrupts.
//
Interrupt_initModule();
//
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
//
Interrupt_initVectorTable();
//
// Set up ADCs, initializing the SOCs to be triggered by software
//
Board_init();
//
// Enable Global Interrupt (INTM) and realtime interrupt (DBGM)
//
EINT;
ERTM;
//
// Loop indefinitely
//
while(1)
{
//
// Convert, wait for completion, and store results
//
ADC_forceMultipleSOC(myADC0_BASE, (ADC_FORCE_SOC0 | ADC_FORCE_SOC1));
//
// Wait for ADCA to complete, then acknowledge flag
//
while(ADC_getInterruptStatus(myADC0_BASE, ADC_INT_NUMBER1) == false)
{
}
ADC_clearInterruptStatus(myADC0_BASE, ADC_INT_NUMBER1);
ADC_forceMultipleSOC(myADC1_BASE, (ADC_FORCE_SOC0 | ADC_FORCE_SOC1));
//
// Wait for ADCC to complete, then acknowledge flag
//
while(ADC_getInterruptStatus(myADC1_BASE, ADC_INT_NUMBER1) == false)
{
}
ADC_clearInterruptStatus(myADC1_BASE, ADC_INT_NUMBER1);
//
// Store results
//
myADC0Result0 = ADC_readResult(ADCARESULT_BASE, ADC_SOC_NUMBER0);
myADC0Result1 = ADC_readResult(ADCARESULT_BASE, ADC_SOC_NUMBER1);
myADC1Result0 = ADC_readResult(ADCCRESULT_BASE, ADC_SOC_NUMBER0);
myADC1Result1 = ADC_readResult(ADCCRESULT_BASE, ADC_SOC_NUMBER1);
DEVICE_DELAY_US(100);
//
// Software breakpoint. At this point, conversion results are stored in
// myADC0Result0, myADC0Result1, myADC1Result0, and myADC1Result1.
//
// Hit run again to get updated conversions.
//
//ESTOP0;
}
}



您好
这里有几个可能的原因和解决方案供你参考:
参考电压和分辨率问题:
1V / 3.3V * 4096(假设参考电压为3.3V且分辨率为12位)的计数值,即约1241。信号源和输入通道问题:
ADC校准和偏移:
噪声和干扰:
代码和配置问题:
为了更具体地诊断问题,你可以尝试以下步骤:
您好
这是影响单片机内部ADC稳定的相关因素,建议您通过上述建议优化。