センサーの値をSORACOMサーバーへ送信したい

Question

3軸加速度センサーとArduino、LTE-M Shield for Arduinoを接続し、センサー値をSORACOMサーバーへ送信したいです。

センサー値の取得及びTeratermでセンサー値を表示することはできるのですが、取得したセンサー値をSORACOMサーバーへ送信する際に値が「？」になってしまい、値を送信することができません。
SORACOMサーバーへの送信用のプログラムはIoTで屋内の環境モニタリングをするを参考にしています。

送信したいセンサー値は符号つき小数点の値（-3.18、-18.90、25.60など）です。

#include <Wire.h>
#include <SoftwareSerial.h> 
#include <stdio.h>

const int LIS3DH_ADDR = 0x18;
const int LIS3DH_ID = 0x33;

const float X_offset = 0.0;
const float Y_offset = 0.0;
const float Z_offset = 0.0;
const float T_offset = -20.0;

volatile uint8_t Int_Detected;

const int AUX_STATUS = 0x07;
const int TEMP_L = 0x0C;
const int TEMP_H = 0x0D;
const int WHO_AM_I = 0x0F;
const int CTRL_REG0 = 0x1E;
const int TEMP_CFG = 0x1F;
const int CTRL_REG1 = 0x20;
const int CTRL_REG2 = 0x21;
const int CTRL_REG3 = 0x22;
const int CTRL_REG4 = 0x23;
const int CTRL_REG5 = 0x24;
const int CTRL_REG6 = 0x25;
const int REFERENCE = 0x26;
const int STATUS = 0x27;
const int XL = 0x28;
const int XH = 0x29;
const int YL = 0x2A;
const int YH = 0x2B;
const int ZL = 0x2C;
const int ZH = 0x2D;
const int FIFO_CTRL = 0x2E;
const int FIFO_SRC = 0x2F;
const int INT1_CFG = 0x30;
const int INT1_SRC = 0x31;
const int INT1_THS = 0x32;
const int INT1_DUR = 0x33;
const int INT2_CFG = 0x34;
const int INT2_SRC = 0x35;
const int INT2_THS = 0x36;
const int INT2_DUR = 0x37;
const int CLICK_CFG = 0x38;
const int CLICK_SRC = 0x39;
const int CLICK_THS = 0x3A;
const int TIME_LIMIT = 0x3B;
const int TIME_LATENCY = 0x3C;
const int TIME_WINDOW = 0x3D;
const int ACT_THS = 0x3E;
const int ACT_DUR = 0x3F;

#define CONSOLE Serial
#define INTERVAL_MS (1000)
#define ENDPOINT "uni.soracom.io"
#define SKETCH_NAME "data_recievetoLTE"
#define VERSION "1.0"

/* for LTE-M Shield for Arduino */
#define RX 10
#define TX 11
#define BAUDRATE 9600
#define BG96_RESET 15

#define TINY_GSM_MODEM_BG96
#include <TinyGsmClient.h>

SoftwareSerial LTE_M_shieldUART(RX, TX);
TinyGsm modem(LTE_M_shieldUART);
TinyGsmClient ctx(modem);


// #define RESET_DURATION 86400000UL // 1 day
void software_reset() {
  asm volatile ("  jmp 0");
}

unsigned int readRegister(byte reg){
  Wire.beginTransmission(LIS3DH_ADDR);
  Wire.write(reg);
  Wire.endTransmission();

  Wire.requestFrom(LIS3DH_ADDR, 1);
  return Wire.read();
}

void writeRegister(byte reg, byte data){
  Wire.beginTransmission(LIS3DH_ADDR);
  Wire.write(reg);
  Wire.write(data);
  Wire.endTransmission();
}

void setup(){
  Wire.begin();
  Serial.begin(19200);

  attachInterrupt(digitalPinToInterrupt(2), activity, FALLING); // INT on D2 pin
//  attachInterrupt(digitalPinToInterrupt(3), activity, RISING); // INT on D3 pin

  writeRegister(TEMP_CFG, 0xC0); // Enable Temperature Sensor
  writeRegister(CTRL_REG1, 0x27); // CTRL_REG1 set to 10Hz !Low_PWR + X&Y&Z
                                  // 0x17:1Hz    0x27:10Hz   0x37:25Hz   0x47:50Hz
                                  // 0x57:100Hz  0x67:200Hz  0x77:400Hz  0x97:1.344kHz
  writeRegister(CTRL_REG4, 0x80); // CTRL_REG4 set to 2G/Normal, Update after Read Data Reg.
                                  // !HR, LSB first/MSB second, Self-test disable.
                                  // 0x80:2G  0x90:4G  0xA0:8G  0xB0:16G

  int res = readRegister(0x0F); // WHO_AM_I
  Serial.print("Addressed Device is ");
  Serial.print(res,HEX);
  Serial.print("H,  ");
  if (res == LIS3DH_ID) Serial.println("OK");
  else Serial.println("NG");
  
  configIntterupts();

  CONSOLE.begin(19200);

  CONSOLE.println();
  CONSOLE.print(F("Welcome to ")); CONSOLE.print(SKETCH_NAME); CONSOLE.print(F(" ")); CONSOLE.println(VERSION);

  CONSOLE.print(F("resetting module "));
  pinMode(BG96_RESET,OUTPUT);
  digitalWrite(BG96_RESET,LOW);
  delay(30);
  digitalWrite(BG96_RESET,HIGH);
  delay(30);
  digitalWrite(BG96_RESET,LOW);
  CONSOLE.println(F(" done."));

  LTE_M_shieldUART.begin(BAUDRATE);

  CONSOLE.print(F("modem.restart()"));
  modem.restart();
  CONSOLE.println(F(" done."));

  CONSOLE.print(F("modem.getModemInfo(): "));
  String modemInfo = modem.getModemInfo();
  CONSOLE.println(modemInfo);

  CONSOLE.print(F("waitForNetwork()"));
  while (!modem.waitForNetwork()) CONSOLE.print(".");
  CONSOLE.println(F(" Ok."));

  CONSOLE.print(F("gprsConnect(soracom.io)"));
  modem.gprsConnect("soracom.io", "sora", "sora");
  CONSOLE.println(F(" done."));

  CONSOLE.print(F("isNetworkConnected()"));
  while (!modem.isNetworkConnected()) CONSOLE.print(".");
  CONSOLE.println(F(" Ok."));

  CONSOLE.print(F("My IP addr: "));
  IPAddress ipaddr = modem.localIP();
  CONSOLE.println(ipaddr);
  
}

void loop(){
  float x, y, z, temp, x1, y1, z1;
  int h, l;
  uint8_t dataRead;
  
  const float Acc_Coefficient = 0.0006125 ; // [mG/digit], for 2G/Normal (FS=00b)

  // read X
  l = readRegister(XL);
  h = readRegister(XH);
  x = h << 8 | l;
  
  // read Y
  l = readRegister(YL);
  h = readRegister(YH);
  y = h << 8 | l;
  
  // read Z
  l = readRegister(ZL);
  h = readRegister(ZH);
  z = h << 8 | l;

  l = readRegister(TEMP_L);
  h = readRegister(TEMP_H);
  temp = h << 8 | l;

  x = x * Acc_Coefficient - X_offset;
  y = y * Acc_Coefficient - Y_offset;
  z = z * Acc_Coefficient - Z_offset;
  temp = temp/256 - T_offset;
  x1 = degrees(asin(x/9.8));
  y1 = degrees(asin(y/9.8));
  z1 = degrees(asin(z/9.8));

  Serial.print("Acc_X = ");　　//ここは正しく表示される
  Serial.print(x);
  Serial.print(",   xd = ");
  Serial.print(x1);
  Serial.print("°,   Acc_Y = ");
  Serial.print(y);
  Serial.print(",   yd = ");
  Serial.print(y1);
  Serial.print("°,   Acc_Z = ");
  Serial.print(z);
  Serial.print(",   zd = ");
  Serial.print(z1);
  Serial.print("°,   TEMP = ");
  Serial.println(temp);

 char payload[120];
 sprintf_P(payload, PSTR("{\"X\":%f,\"Y\":%f,\"Z\":%f,\"temp\":%f}"), x1, y1, z1, temp); //送るデータ「？」になる
 CONSOLE.println(payload);

    if (!ctx.connect(ENDPOINT, 80)) {
    CONSOLE.println(F("failed."));
    delay(30);
    return;
  }

  /*send request*/ 
  char hdr_buf[40];
  ctx.println(F("POST / HTTP/1.1"));
  sprintf_P(hdr_buf, PSTR("Host: %s"), ENDPOINT);
  ctx.println(hdr_buf);
  ctx.println(F("Content-Type: application/json"));
  ctx.println(hdr_buf);
  ctx.println();
  while (ctx.connected()) {
    String line = ctx.readStringUntil('\n');
    CONSOLE.println(line);
    if (line == "\r") {
      CONSOLE.println(F("Response header received."));
      break;
    }
  }
  
  ctx.stop();

  delay(INTERVAL_MS);

  #ifdef RESET_DURATION
  if(millis() > RESET_DURATION )
  {
    CONSOLE.println("Execute software reset...");
    delay(10);
    software_reset();
  }
#endif
}

void configIntterupts()
{
  uint8_t dataToWrite = 0;
  dataToWrite |= 0x10;//Z low

  writeRegister(INT1_CFG, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x10; // 1/8 range
  writeRegister(INT1_THS, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x01; // 1 * 1/50 s = 20ms
  writeRegister(INT1_DUR, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x10;//Z single-click
  dataToWrite |= 0x04;//Y single-click
  dataToWrite |= 0x01;//X single-click
  writeRegister(CLICK_CFG, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x04;//Enable single clicks
  dataToWrite |= 0x04;//Z click detect enabled
  dataToWrite |= 0x02;//Y click detect enabled
  dataToWrite |= 0x01;//X click detect enabled
  writeRegister(CLICK_SRC, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x0A; // ~1/16 range <- 1/12.7
  writeRegister(CLICK_THS, dataToWrite);
  
  dataToWrite = 0;
  dataToWrite |= 0x08; // 8 * 1/50 s = 160ms
  writeRegister(TIME_LIMIT, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x08; // 4 * 1/50 s = 160ms
  writeRegister(TIME_LATENCY, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x10; // 16 * 1/50 s = 320ms
  writeRegister(TIME_WINDOW, dataToWrite);

  dataToWrite = readRegister(CTRL_REG5);
  dataToWrite &= 0xF3; //Clear bits of interest
  dataToWrite |= 0x08; //Latch interrupt (Cleared by reading int1_src)
  writeRegister(CTRL_REG5, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x80; //Click detect on pin 1
  dataToWrite |= 0x40; //AOI1 event (Generator 1 interrupt on pin 1)
  dataToWrite |= 0x20; //AOI2 event ()
  writeRegister(CTRL_REG3, dataToWrite);

  dataToWrite = 0;
  dataToWrite |= 0x80; //Click int on pin 2
  writeRegister(CTRL_REG6, dataToWrite);
  
}

void activity()
{

  Int_Detected = 1 ; // Set interruput detection flag 
}

試したこと

・payload内の変換指定子を一通り試しましたが、正しい値を送信できませんでした。
・各センサー値をfloat型からchar型に変換してみましたが、うまく変換できないようで、こちらも「？」の表示となってしまいます。

  char x2[50];
  snprintf(x2,50,"%f", x1);
  puts(x2);
  Serial.println(x2);  //←？の表示となる

データは取得出来ているので、送付する部分のプログラムが違うのだと思うのですが、どの部分を修正したらよいのかアドバイスいただきたいです。

よろしくお願いいたします。

Answer 1

arduinoのsprintfはfloat/doubleに非対応。
dtostrfとかで変換する。

Comments

[senntii]

dtostrfで変換したらいけました。
sprintfはArduinoではfloat/doubleに非対応ということを初めて知りました。

ありがとうございました。