That was my initial thought as well but I have them stored as a float so I am not sure what the issue is. I have posted my code below:
#include <XBee.h>
#include <SoftwareSerial.h>
#include <AltSoftSerial.h>
#include <SPI.h>
#include <SD.h>
//import the xbee, software serial, SPI, and SD card libraries
XBee xbee = XBee();
XBeeResponse response = XBeeResponse();
Rx16IoSampleResponse rx16 = Rx16IoSampleResponse();
//define the two pins used for data transmission
//Dout on the XBee goes to pin 2 and Din goes to pin 3
#define ssRX 2
#define ssTX 3
SoftwareSerial lcd(ssRX, ssTX);
AltSoftSerial xbeeserial;
//variables for each of the four sensor values, the SD card, and the button
float data = 0;
float data2 = 0;
float data3=0;
float data4=0;
float front=0;
float back=0;
const int button1Pin = 4; // pushbutton 1 pin
int button1State;
const int chipSelect = 10;
void setup() {
// Set up the pushbutton and sd card pins:
pinMode(button1Pin, INPUT);
pinMode(chipSelect, OUTPUT);
// start serial
Serial.begin(9600);
// and the software serial port
lcd.begin(9600);
// now that they are started, hook the XBee into
// Software Serial
xbeeserial.begin(9600); //new
xbee.setSerial(xbeeserial);
lcd.print(" ");
Serial.println("starting up!");
// see if the card is present and can be initialized:
if (!SD.begin(chipSelect)) {
Serial.println("Card failed, or not present");
// don't do anything more:
return;
}
Serial.println("card initialized.");
}
void loop() {
xbee.readPacket();
//Serial.println("test");
if (xbee.getResponse().isAvailable()) {
// got something
Serial.println();
Serial.print("Frame Type is ");
Serial.println(xbee.getResponse().getApiId(), HEX);
if (xbee.getResponse().getApiId() == RX_16_IO_RESPONSE) {
xbee.getResponse().getRx16IoSampleResponse(rx16);
//prints the analog values from each of the sensors
data = rx16.getData(4);
data2=rx16.getData(6);
data3=rx16.getData(8);
data4=rx16.getData(10);
//data=data3.0/265.0;
//data2=data23.0/265.0;
//data3=data33.0/265.0;
//data4=data43.0/265.0;
front=data + data2;
back=data3+data4;
float sensorVoltageF = front * (3.0 / 1023.0);
float sensorVoltageB= back* (3.0/1023.0);
//double voltage2Pound = 6.8723sensorVoltagesensorVoltagesensorVoltage - 3.7445sensorVoltagesensorVoltage + 7.1943sensorVoltage - .2046;
if (front != 0){
lcd.print("Frnt(lbs): ");
lcd.println(front);
} else if (back != 0){
lcd.print("Back(lbs): ");
lcd.println(back);
}
else{
lcd.println("No Force ");
}
String dataString = "";
dataString += String(sensorVoltageF);
Serial.println(front);
Serial.println(back);
//dataString += " ";
//dataString += String(sensorVoltageB);
button1State = digitalRead(button1Pin);
if (button1State == HIGH){
// open the file. note that only one file can be open at a time,
// so you have to close this one before opening another.
File dataFile = SD.open("DATALOG.txt", FILE_WRITE);
// if the file is available, write to it:
if (dataFile) {
dataFile.println(dataString);
dataFile.close();
// print to the serial port too:
Serial.println(dataString);
}
// if the file isn't open, pop up an error:
else {
Serial.println("error opening DATALOG.txt");
}
}
}
else if (xbee.getResponse().isError()) {
Serial.print("Error reading packet. Error code: ");
Serial.println(xbee.getResponse().getErrorCode());
}
}
}