c - 如何使用这个 Arduino 演示串行读取更大的数据类型？

Question

我很难理解我的数据类型的大小与通过 Arduino mega2560 解析串行信息的关系。我正在尝试通过串行监视器输入大整数，例如整数 8000000，但正在返回负数或明显更小的数字。

下面的代码是我修改的一个demo。用户必须继续并结束小于和大于符号 (<'NUMBER>) 之间的串行输入：

const byte numChars = 32;
char receivedChars[numChars];
char tempChars[numChars];        // temporary array for use by strtok() function

// variables to hold the parsed data
char messageFromPC[numChars] = {0};
int integerFromPC = 0;
float floatFromPC = 0.0;

boolean newData = false;

//============

void setup() {
    Serial.begin(9600);
    // Serial.println("This demo expects 3 pieces of data - text, an integer and a floating point value");
    // Serial.println("Enter data in this style <text,12,24.7>  ");
    Serial.println();
}

//============

void loop() {
    recvWithStartEndMarkers();
    if (newData == true) {
        strcpy(tempChars, receivedChars);
            // this temporary copy is necessary to protect the original data
            //   because strtok() replaces the commas with \0
        parseData();
        showParsedData();
        newData = false;
    }
}

//============

void recvWithStartEndMarkers() {
    static boolean recvInProgress = false;
    static byte ndx = 0;
    char startMarker = '<';
    char endMarker = '>';
    char rc;

    while (Serial.available() > 0 && newData == false) {
        rc = Serial.read();

        if (recvInProgress == true) {
            if (rc != endMarker) {
                receivedChars[ndx] = rc;
                ndx++;
                if (ndx >= numChars) {
                    ndx = numChars - 1;
                }
            }
            else {
                receivedChars[ndx] = '\0'; // terminate the string
                recvInProgress = false;
                ndx = 0;
                newData = true;
            }
        }

        else if (rc == startMarker) {
            recvInProgress = true;
        }
    }
}

//============

void parseData() {

      // split the data into its parts
    char * strtokIndx; // this is used by strtok() as an index

    // strtokIndx = strtok(tempChars,",");      // get the first part - the string
    // strcpy(messageFromPC, strtokIndx); // copy it to messageFromPC

    strtokIndx = strtok(tempChars, ","); // this continues where the previous call left off
    integerFromPC = atoi(strtokIndx);     // convert this part to an integer

    // strtokIndx = strtok(NULL, ",");
    // floatFromPC = atof(strtokIndx);     // convert this part to a float

}

//============

void showParsedData() {
    Serial.print("Message ");
    Serial.println(messageFromPC);
    Serial.print("Integer ");
    Serial.println(integerFromPC);
    Serial.print("Float ");
    Serial.println(floatFromPC);
}

我怀疑我的问题与变量的数据类型有关。

标签： carduino