Question

我正在北欧Micro创建一个项目，它从模拟输入termninal中读取一个值，并将其输出到UART中。我现在正尝试使用GE Proficy Historian Compression压缩数据，以便只在UART中输出更改的数据。但我的代码不起作用。输出的数据有时仍然是多余的。该程序的想法是每隔一段时间生成一个中断，读取adc值，如果它与先前值不同，则将其输出到UART端口。这里解释了算法 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;

Answer 1

谢谢大家的贡献，主要是@Weather Vane。正如你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，这使得它无法正常运行。我现在通过将代码的各部分分散到主函数来修复问题。 Regareds

C中的简单压缩算法不起作用..有什么建议吗？

1 个答案: