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我正在 Nordic Micro 中创建一个项目，该项目从模拟输入终端读取值并将其输出到 UART。我现在正在尝试使用 GE Proficy Historian Compression 压缩数据，以便在 UART 中仅输出更改的数据。但是我的代码不起作用。输出的数据有时仍然是多余的。该程序的想法是每隔一定时间产生一个中断，读取 adc 值，如果它与之前的值不同，则将其输出到 UART 端口。该算法在这里解释 http://www.evsystems.net/files/GE_Historian_Compression_Overview.ppt 处理中断的代码的主要部分如下所示

void ADC_IRQHandler(void)
{
    /* Clear dataready event */
  NRF_ADC->EVENTS_END = 0;   
    // write ADC value to UART port 

    // Compression Algorithm should occur here
    uint8_t current_Val= NRF_ADC->RESULT;
    //simple_uart_put(current_evaluation);


    // Construct error bands around the held point

    float U_tolerance = current_Val  + error_tolerance;
    float L_tolerance = current_Val - error_tolerance; // integer type is selected since lower tolerance could be negative

    if( first_Run == false)
    {
        float slope = ((current_Val - Archived_Val) / (held_Time - Archived_Time)) ;
        if (slope > U_Slope || slope > L_Slope)
        {
            Archived_Val = current_Val; // update the archived value
            held_Time = 1; // reset held time
            simple_uart_put(current_Val);
            first_Run = true;
            Archived_Val = current_Val;
        }
        else
        {
            float Upper_Slope = (U_tolerance - Archived_Val) /( held_Time - Archived_Time);
            float Lower_Slope  = (L_tolerance - Archived_Val)/(held_Time- Archived_Time);

            if(Upper_Slope < U_Slope) // lowest upper slope is always taken as a blanket boundry
            {
                U_Slope = Upper_Slope;
            }
            if(Lower_Slope < L_Slope)
            {
                L_Slope = Lower_Slope;
            }
            held_Time += time_increment;
        }
    }

    if (first_Run == true) // first held point always outputted
    {
            // calculate the slopes of the two lines 
    float Upper_Slope = (U_tolerance - Start_Up_Val) /( held_Time - Archived_Time);
    float Lower_Slope  = (L_tolerance - Start_Up_Val)/(held_Time- Archived_Time);

        // Update Max and Min slopes

    if(Upper_Slope < U_Slope) // lowest upper slope is always taken as a blanket boundry
    {
            U_Slope = Upper_Slope;
    }
    if(Lower_Slope < L_Slope)
    {
        L_Slope = Lower_Slope;
    }


    held_Time += time_increment;
    first_Run = false;
    Archived_Val = current_Val;
    }

}

变量定义如下

> uint32_t error_tolerance = 50; // error tolerance value for swining door algorithm
uint8_t Start_Up_Val = 100;
float held_Time = 1;
int Archived_Time = 0;
float U_Slope = 2500;
float L_Slope = 0;
//float slope;
uint8_t Archived_Val;
bool GE_Comp(uint8_t, uint8_t, uint8_t, int);
bool first_Run = true;
float time_increment = 0.1;
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1 回答 1

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感谢大家的贡献，主要是感谢@Weather Vane。正如您和其他人所建议的那样，中断处理程序正在执行过多的编码，从而使其无法正常工作。我现在按照建议通过将代码的各个部分分散到主要功能来解决问题。问候

于 2015-09-07T06:20:22.370 回答