# FSR Code With Excel (PLX-DAQ)

Hallo,

i need help with this code `````` /* FSR testing sketch.

int zahl =0;
int fsrPin = 0;     // the FSR and 10K pulldown are connected to a0
int fsrVoltage;     // the analog reading converted to voltage
unsigned long fsrResistance;  // The voltage converted to resistance, can be very big so make "long"
unsigned long fsrConductance;
long fsrForce;       // Finally, the resistance converted to force

void setup(void) {
Serial.begin(9600);   // We'll send debugging information via the Serial monitor
Serial.println("CLEARDATA");
}

void loop(void) {
zahl++;

// analog voltage reading ranges from about 0 to 1023 which maps to 0V to 5V (= 5000mV)
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);

if (fsrVoltage == 0) {
Serial.println("No pressure");
} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V        yay math!
fsrResistance = 5000 - fsrVoltage;     // fsrVoltage is in millivolts so 5V = 5000mV
fsrResistance *= 10000;                // 10K resistor
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);

fsrConductance = 1000000;           // we measure in micromhos so
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);

// Use the two FSR guide graphs to approximate the force
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
}
}
Serial.println("--------------------");
Serial.print("DATA,DATE,TIME," + String(zahl) +","+ String(fsrReading) +","+ String(fsrVoltage) +","+ String(fsrResistance) +","+ String(fsrConductance) +","+ String(fsrForce));

delay(1000);
}
``````

``````int zahl =0;
int fsrPin = 0;     // the FSR and 10K pulldown are connected to a0
int fsrVoltage;     // the analog reading converted to voltage
unsigned long fsrResistance;  // The voltage converted to resistance, can be very big so make "long"
unsigned long fsrConductance;
long fsrForce;       // Finally, the resistance converted to force

void setup(void) {
Serial.begin(9600);   // We'll send debugging information via the Serial monitor
Serial.println("CLEARDATA");
}

void loop(void) {
zahl++;

// analog voltage reading ranges from about 0 to 1023 which maps to 0V to 5V (= 5000mV)
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);

if (fsrVoltage == 0) {
Serial.println("No pressure");
} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V        yay math!
fsrResistance = 5000 - fsrVoltage;     // fsrVoltage is in millivolts so 5V = 5000mV
fsrResistance *= 10000;                // 10K resistor
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);

fsrConductance = 1000000;           // we measure in micromhos so
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);

// Use the two FSR guide graphs to approximate the force
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
}
}
Serial.println("--------------------");
Serial.print("DATA,DATE,TIME," + String(zahl) +","+ String(fsrReading) +","+ String(fsrVoltage) +","+ String(fsrResistance) +","+ String(fsrConductance) +","+ String(fsrForce));

delay(1000);
}
``````

Hey thanks,
I want me to import the results to the Excel file (PLX-DAQ), but I get the columns swapped and together (look pic1).

I want that I have 6 columns and each column has its own result (like pic2)

What exactly do you define as wrong? Could you post some output from your program and describe what readings you believe are erroneous?

Also, from the PLX_DAQ website… are you aware the software is no longer supported? Have you tried PLX_DAQ with any other micro-controller successfully? It looks like Parallax developed the software for use only with their controllers. I’m not sure what is proprietary about it so do you know if it will work with Particle devices? i use now arduino and it works good but I get the measured values (analog reading) twice
i dont know why?(look PIC)

this is my Code

``````int zahl =0;
int fsrPin = 0;     // the FSR and 10K pulldown are connected to a0
int fsrVoltage;     // the analog reading converted to voltage
unsigned long fsrResistance;  // The voltage converted to resistance, can be very big so make "long"
unsigned long fsrConductance;
long fsrForce;       // Finally, the resistance converted to force

void setup(void) {
Serial.begin(9600);   // We'll send debugging information via the Serial monitor
Serial.println("CLEARSHEET");

}

void loop(void) {
zahl++;

// analog voltage reading ranges from about 0 to 1023 which maps to 0V to 5V (= 5000mV)
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);

if (fsrVoltage == 0) {
Serial.println("No pressure");
} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V        yay math!
fsrResistance = 5000 - fsrVoltage;     // fsrVoltage is in millivolts so 5V = 5000mV
fsrResistance *= 10000;                // 10K resistor
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);

fsrConductance = 1000000;           // we measure in micromhos so
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);

// Use the two FSR guide graphs to approximate the force
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
}

}
Serial.println("----------------------------------------------------------------");

Serial.print("DATA,DATE,TIME," + String(zahl) +","+ String(fsrForce) +","+ String(fsrVoltage) +","+ String(fsrResistance) +","+ String(fsrConductance) +","+ String(fsrReading));

delay(1000);
}
``````  Both are `serial.print()` statements. So the first `serial.print()` in loop is just tacking onto whatever the last `serial.print()` was sending. You need to include a `serial.println()` as the last line in loop() to stop that behavior.

Regarding the column order on the spreadsheets, I’m not sure if this is the appropriate forum for your quesitons. I’ll explain… I pic 1, I see the columns in the same order as you are publishing in your loop. Only at the bottom of your loop do you publish a consolidated line with the data string in a different order. It looks like at the start of that consolidated println you have 3 column headers. I don’t know anything about how PLX_DAQ accepts the data and plots it to the appropriate columns. As far as I can tell, your code and Particle device are functioning appropriately. Are you not able to edit the sheet to place the columns where you want them? If not, you probably want to ask these questions in a forum dedicated to Parallax or PLX_DAQ.

Perhaps an Elite (@ScruffR, @Moors7, @bko, @peekay123) could split your comments from this thread into its own thread because your questions are not related to the original post’s problems. Your issue is with an external 3rd-party software.

3 Likes

I love You
Thanks           Hey bro,

can you tell me Pleaase why i got the Offset in the 3 Columms of ( Force, fsrConductance and fsrResistance) ??? Look the Pic please

the Voltage an the analog read are is zero, thats mean there are no Force !!!

Not entirely sure, but since you are not setting new values for any of your variables in case of …

``````if (fsrVoltage == 0) {
Serial.println("No pressure");
} else {
... // new values would be produced here but doesn't happen if fsrVoltage == 0
}
Serial.println("----------------------------------------------------------------");

Serial.print("DATA,DATE,TIME," + String(zahl) +","+ String(fsrForce) +","+ String(fsrVoltage) +","+ String(fsrResistance) +","+ String(fsrConductance) +","+ String(fsrReading));
``````

… but still print out the old values, I’d think you are seeing artefacts of previous readings.

BTW, since Particle devices use 12bit ADCs your mapping of the analog value should probably be using `4095` instead of `1023` (10bit) and having said that 4095 equals 3300mV not 5000.

2 Likes

I agree w/ @ScruffR on all points.

Change your top-most if-else-statement to something like this:

``````if (fsrVoltage == 0) {
Serial.println("No pressure");
fsrResistance = 0;
fsrForce = 0;
fsrConductance = 0;
} else {
``````

You don’t have to set those values to 0 but I’m not sure what the default (or no-reading) values should be. If it were me, I’d just set them all to 0 so I know it’s erroneous data.

1 Like

thanks thanks i will do it

Thanks for Your help   1 Like

thanks thanks i will do it

Thanks for Your help    Hey again, sorry for botter you but im not good in programming can you tell me why i got this Mistake ??? look Pic please

the code is here    ``````#include <SD.h>
#include <SPI.h>
File myFile;
long id =1;

int fsrPin = 0;     // the FSR and 10K pulldown are connected to a0
int fsrVoltage;     // the analog reading converted to voltage
unsigned long fsrResistance;  // The voltage converted to resistance, can be very big so make "long"
unsigned long fsrConductance;
long fsrForce;       // Finally, the resistance converted to force

void setup(void) {
Serial.begin(9600);   // We'll send debugging information via the Serial monitor
// SD Card Initialization
if (SD.begin(10))
{
Serial.println("SD card is ready to use.");
} else
{
Serial.println("SD card initialization failed");
return;
}
File myFile = SD.open("test.txt", FILE_WRITE);
if (myFile)
{
myFile.close();
} else {
Serial.println("error opening test.txt");
}
}

void loop(void) {

// analog voltage reading ranges from about 0 to 1023 which maps to 0V to 5V (= 5000mV)
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);

if (fsrVoltage == 0) {
Serial.println("No pressure");
} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V        yay math!
fsrResistance = 5000 - fsrVoltage;     // fsrVoltage is in millivolts so 5V = 5000mV
fsrResistance *= 10000;                // 10K resistor
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);

fsrConductance = 1000000;           // we measure in micromhos so
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);

// Use the two FSR guide graphs to approximate the force
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);
}
}
File myFile = SD.open("test.txt", FILE_WRITE);
if (myFile) {
myFile.print(",");
myFile.println(fsrVoltage);
myFile.print(",");
myFile.println(fsrResistance);
myFile.print(",");
myFile.println(fsrConductance);
myFile.print(",");
myFile.println(fsrForce);
myFile.close();
} else {
Serial.println("error opening test.txt");
}
Serial.println("--------------------");

id++;
delay(1000);
}
``````

thanks For Your best Help Only the above line should be a println statement. All the other print statements, within that if block, should just be myFile.Print.

2 Likes

thanks thanks for your Help but why i got the Header double ???

thanks again

Probably since you are writing into a file that already contained data and don’t make sure to overwrite potentially existing data in said file.

In your `setup()` you are using `FILE_WRITE` which is defined as

``````/** Arduino SD.h style flag for open at EOF for read/write with create. */
#define FILE_WRITE (O_RDWR | O_CREAT | O_AT_END)
``````

but should use `(O_CREAT | O_TRUNC | O_WRITE)` to open and truncate or create a new file for write access.

4 Likes

thanks for Your all Helping i have still last quetion:

why I getting 0 if I have already written the if function loook pic Please

the Code:

``````/*
Connect one end of FSR to power, the other end to Analog 0.
Then connect one end of a 10K resistor from Analog 0 to ground
*/

int zahl =0;
int fsrPin = 0;     // the FSR and 10K pulldown are connected to a0
int fsrVoltage;     // the analog reading converted to voltage
unsigned long fsrResistance;  // The voltage converted to resistance, can be very big so make "long"
unsigned long fsrConductance;
long fsrForce;  // Finally, the resistance converted to force
float Pressure = 0;       // Finally, the N converted to mmHg

void setup(void) {
Serial.begin(9600);   // We'll send debugging information via the Serial monitor
Serial.println("CLEARSHEET");

}

void loop(void) {

zahl++;

// analog voltage reading ranges from about 0 to 1023 which maps to 0V to 5V (= 5000mV)
fsrVoltage = map(fsrReading, 0, 1023, 0, 5000);
Serial.print("Voltage reading in mV = ");
Serial.println(fsrVoltage);

if (fsrVoltage == 0) {
Serial.println("No pressure");

//um Offset zu verhindern, wenn fsrVoltage == 0
fsrResistance = 0;
fsrForce = 0;
fsrConductance = 0;

} else {
// The voltage = Vcc * R / (R + FSR) where R = 10K and Vcc = 5V
// so FSR = ((Vcc - V) * R) / V        yay math!
fsrResistance = 5000 - fsrVoltage;     // fsrVoltage is in millivolts so 5V = 5000mV
fsrResistance *= 10000;                // 10K resistor
fsrResistance /= fsrVoltage;
Serial.print("FSR resistance in ohms = ");
Serial.println(fsrResistance);

fsrConductance = 1000000;           // we measure in micromhos so
fsrConductance /= fsrResistance;
Serial.print("Conductance in microMhos: ");
Serial.println(fsrConductance);

// Use the two FSR guide graphs to approximate the force
if (fsrConductance <= 1000) {
fsrForce = fsrConductance / 80;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);

} else {
fsrForce = fsrConductance - 1000;
fsrForce /= 30;
Serial.print("Force in Newtons: ");
Serial.println(fsrForce);

}
if (fsrForce >= 1){
Pressure = fsrForce/176;
Serial.print("Pressure in mmHg: ");
Serial.println(Pressure);
}

else {
}
}

Serial.print("DATA,DATE,TIME," + String(zahl) +","+ String(fsrReading) +","+ String(fsrVoltage) +","+ String(fsrResistance) +","+ String(fsrConductance) +","+ String(fsrForce)+","+ String(Pressure));
Serial.println();
Serial.println("----------------------------------------------------------------");

delay(1000);
}
``````

Try writing `Pressure = fsrForce/176.0;` instead.
Without the final `.0` both variables are integer types and hence you’ll get an integer result even if storing the result in a `float`. And since the result will be less than 1 you’ll only ever get 0.

4 Likes   Thanks Thanks
best guys of World  2 Likes

i got the result with point thanks @ScruffR but can i get the result for Pressure through arduino Like the Pic ?? so i mean the arduino give me only the first two Points but i need all Point (or 4 points) to show me

i did calculate with excel then it give me the correct result but arduino not is there any idea

a thanks 