Hello all. I have the following code. For the frequency counter part - it works fine on its own. For the Datalogger/Thermistor part - works pretty good on its own. Put the two together....all of a sudden everything works great except for the frequency reading. Any coders know where I've gone wrong?
#include <math.h>
#include <SD.h>
#include "Wire.h"
#include "RTClib.h"
#include <FreqCounter.h>
//---------------------------
//---------------------------
// A simple data logger for the Arduino analog pins
#define LOG_INTERVAL 1000 // mills between entries
#define ECHO_TO_SERIAL 1 // echo data to serial port
#define DS1307_I2C_ADDRESS 0x68 // This is the I2C address
const int chipSelect = 10;
RTC_DS1307 RTC;
// the logging file
File datafile;
byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
//--------------
//--------------
void setup(void) {
Serial.begin(9600);
Serial.println();
Wire.begin();
// initialize the SD card
Serial.print("Initializing SD card...");
pinMode(10, OUTPUT);
// 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.");
}
//-----------------------------------
//-----------------------------------
//Reference Voltage
long readVcc() {
long result;
// Read 1.1V reference against AVcc
ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
delay(2); // Wait for Vref to settle
ADCSRA |= _BV(ADSC); // Convert
while (bit_is_set(ADCSRA,ADSC));
result = ADCL;
result |= ADCH<<8;
result = 1125300L / result; // Back-calculate AVcc in mV
return result;
}
String printDouble( double val, unsigned int precision){
// prints val with number of decimal places determine by precision
// example: printDouble( 3.1415, 100); // prints 3.14 (two decimal places)
String retval;
retval += String(int(val));
retval += ".";
unsigned int frac;
if(val >= 0)
frac = (val - int(val)) * precision;
else
frac = (int(val)- val ) * precision;
retval += frac;
return retval;
}
//--------------------
//--------------------
float pad = 2267; // balance/pad resistor value
float thermr = 2001; // thermistor nominal resistance
double Thermister(int RawADC) {
delay(100);
long Resistance;
float Temp; // Dual-Purpose variable to save space.
Resistance=((1024 * pad / RawADC) - pad);
Temp = log(Resistance); // Saving the Log(resistance) so not to calculate it 4 times later
Temp = 1 / (0.00032939375 + (0.00044329916 * Temp) + (-0.00000077648923 * Temp * Temp * Temp));
Temp = Temp - 273.15; // Convert Kelvin to Celsius
double Vcc=readVcc()/1000.0;
#if ECHO_TO_SERIAL
Serial.print("ADC: ");
Serial.print(RawADC);
Serial.println("/1024"); // Print out RAW ADC Number
Serial.println(" Kohms");
Serial.print("Volts: ");
Serial.println(((RawADC*Vcc)/1024.0),3);
Serial.print("Resistance: ");
Serial.print(Resistance);
Serial.println(" ohms ");
#endif
return Temp;
}
//-----------------------------------------
//-----------------------------------------
void printTherm(void) {
double therm = Thermister(analogRead(0)); // Read sensor
#if ECHO_TO_SERIAL
Serial.print("Therm Temperature is: ");
Serial.print(therm,2);
Serial.print((char)176);("Date, Time, Freq, ThermT");
Serial.println("");
#endif //end ECHO_TO_SERIAL
}
//---------------------------------------------------------
//---------------------------------------------------------
void loop(void) {
//detect frequency input from pressure transducer
delay (50);
long int frq;
FreqCounter::f_comp = 8;
FreqCounter::start(1000);
while (FreqCounter::f_ready == 0)
frq=FreqCounter::f_freq;
delay(50);
//-----------------------------------------------------
//------------------------------------------------------
// make a string for assembling the data to log:
String dataString = getDateDs1307();
dataString += String(", ");
dataString += String(frq);
//String sensor2 = (frq,1);
//dataString += sensor2;
dataString += ", ";
String sensor1 = printDouble (Thermister(analogRead(0)),100);
dataString += sensor1;
dataString += ", ";
#if ECHO_TO_SERIAL
printTherm();
Serial.print("Frequency: ");
Serial.println(frq);
// printTemp();
#endif
File dataFile = SD.open("logger.csv", FILE_WRITE);
if (dataFile)
{
datafile.println(", , , ,");///just a blank line
datafile.println("Date, Time, Freq, ThermT");
datafile.close();
dataFile.println(dataString);
dataFile.close();
// print to the serial port too:
#if ECHO_TO_SERIAL
Serial.println("\nDate, Time, Freq, ThermT");
Serial.println(dataString);
Serial.println("");
#endif
}
// if the file isn't open, pop up an error:
else
{
Serial.println("error opening test.csv");
}
delay(20000);
}
//-----------------------------------------------------
//-----------------------------------------------------
void setDateDs1307()
{
// Use of (byte) type casting and ascii math to achieve result.
second = (byte) ((Serial.read() - 48) * 10 + (Serial.read() - 48));
minute = (byte) ((Serial.read() - 48) *10 + (Serial.read() - 48));
hour = (byte) ((Serial.read() - 48) *10 + (Serial.read() - 48));
dayOfWeek = (byte) (Serial.read() - 48);
dayOfMonth = (byte) ((Serial.read() - 48) *10 + (Serial.read() - 48));
month = (byte) ((Serial.read() - 48) *10 + (Serial.read() - 48));
year= (byte) ((Serial.read() - 48) *10 + (Serial.read() - 48));
Wire.beginTransmission(DS1307_I2C_ADDRESS);
Wire.write(byte(0x00));
Wire.write(decToBcd(second)); // 0 to bit 7 starts the clock
Wire.write(decToBcd(minute));
Wire.write(decToBcd(hour)); // If you want 12 hour am/pm you need to set
// bit 6 (also need to change readDateDs1307)
Wire.write(decToBcd(dayOfWeek));
Wire.write(decToBcd(dayOfMonth));
Wire.write(decToBcd(month));
Wire.write(decToBcd(year));
Wire.endTransmission();
}
String getDateDs1307()
{
// Reset the register pointer
Wire.beginTransmission(DS1307_I2C_ADDRESS);
Wire.write(0x00);
Wire.endTransmission();
Wire.requestFrom(DS1307_I2C_ADDRESS, 7);
// A few of these need masks because certain bits are control bits
second = bcdToDec(Wire.read() & 0x7F);
minute = bcdToDec(Wire.read());
hour = bcdToDec(Wire.read() & 0x3F);
dayOfWeek = bcdToDec(Wire.read());
dayOfMonth = bcdToDec(Wire.read());
month = bcdToDec(Wire.read());
year = bcdToDec(Wire.read());
String dataString = "";
dataString += Print2Digit(dayOfMonth);
dataString += String("/");
dataString += Print2Digit(bcdToDec(month));
dataString += String("/"); // Y2k1 bug!
dataString += Print2Digit(bcdToDec(year));
dataString += String(", ");
dataString += Print2Digit(hour);
dataString += String(":");
dataString += Print2Digit(minute);
dataString += String(":");
dataString += Print2Digit(second);
return dataString;
}
//-------------------------------------------------
//-------------------------------------------------
// Convert binary coded decimal to normal decimal numbers
byte bcdToDec(byte val)
{
return ( (val/16*10) + (val%16) );
}
// Convert normal decimal numbers to binary coded decimal
byte decToBcd(byte val)
{
return ( (val/10*16) + (val%10) );
}
String Print2Digit(byte Val)
{
String dataString = "";
if (Val < 10)
{
dataString = "0";
}
dataString += String(Val, DEC);
return dataString;
}
Code:
FreqCounter::start(1000);
while (FreqCounter::f_ready == 0)
{/* DO NOTHING */}
frq=FreqCounter::f_freq;
I hadn't realized that the space in between made the difference. Although, now that I have fixed that it seems to not have made any difference. My readings are jumpy and incorrect. Could it be a problem with noise? or a problem with the readings interfering with each other?
Code:
FreqCounter::start(1000);
while (FreqCounter::f_ready == 0)
{/* DO NOTHING */}
frq=FreqCounter::f_freq;
I hadn't realized that the space in between made the difference. Although, now that I have fixed that it seems to not have made any difference. My readings are jumpy and incorrect. Could it be a problem with noise? or a problem with the readings interfering with each other?
The space does not. What he wrote is equivalent to:
FreqCounter::start(1000);
while (FreqCounter::f_ready == 0); // the loop ENDS at the test, if true it loops again
frq=FreqCounter::f_freq;
What you wrote is easier read as:
FreqCounter::start(1000);
while (FreqCounter::f_ready == 0)
{
frq=FreqCounter::f_freq;
}
If you -always- put in the brackets -always- at the same indent level THEN
it will -always- be easier to check your code.
Try running the old frequency sketch just to see if the wiring has not changed.
Try running the old frequency sketch just to see if the wiring has not changed.
I ran the old sketch again and was getting the correct results. Unfortunately its when I combine the frequency sketch with the datalogger sketch that everything goes wrong with the frequency reading.
I'm thinking it might have something to do with timing. Or could it be that I am using the ARef pin on the arduino to help level shift my frequency circuit, and I am doing the following for the reference voltage reading:
long readVcc() {
long result;
// Read 1.1V reference against AVcc
ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
delay(2); // Wait for Vref to settle
ADCSRA |= _BV(ADSC); // Convert
while (bit_is_set(ADCSRA,ADSC));
result = ADCL;
result |= ADCH<<8;
result = 1125300L / result; // Back-calculate AVcc in mV
return result;
}
I don't know, I don't have your hardware and don't want to dig through the libraries.
The wiring is okay and the parts are okay alone. If the frequency reader depends on interrupts and the Wire part also runs on interrupts then you might want to turn each one off while the other is running.
If the frequency reader depends on interrupts and the Wire part also runs on interrupts then you might want to turn each one off while the other is running.
I am unsure if I am able to do this as the Freq Counter part is coded in the .cpp file, which I am inexperienced to be able to decipher.
Can a .cpp file be created into its own function and then called in the main program void loop? Would that perhaps fix the problem?
It could get you frequency but no amplitude or wave shape. To use a rising edge interrupt you might have to use some extra electronics (beyond my know how).
It could get you frequency but no amplitude or wave shape. To use a rising edge interrupt you might have to use some extra electronics (beyond my know how).
What kind of frequencies are you looking at?
Frequency is all I need. The frequency I am looking at is 36kHz-38kHz. I have a level shifter circuit hooked up to keep my wave above 0.
Is there an example of the sketch that you are thinking of that I could take a look at?
I had a look to see what I could crank out to test since I don't have a solid frequency source, but I do have 2 UNO's. The thing about UNO's is that the 328P oscillator is a resonator so solid is relative. So what should have generated and received 50k Hz tells me 46761 Hz. There is also some error in that micros() is only good to 4 usecs, but that's small.
An RTC (and more code) can help or after making sure the error is always the same (changes due to temperature I think), a correction in software, -or- someone spotting a fixable error in my routines.
Here's my reader sketch, pulse input is to pin 2. Note the turn on/off code is in there.
You could try this out with your pressure source just to see what you get.
Here's my reader sketch, pulse input is to pin 2. Note the turn on/off code is in there.
You could try this out with your pressure source just to see what you get.
@GoForSmoke
It seems to be giving me the same readings I was getting from the FreqCounter sketch. Your sketch is far easier for me to understand as well. My coding experience is very limited, so this has been a great help. Thank you.
I will next try and combine this with the datalogging sketch and see how it goes.
The problem is happening again when I merge the two codes together. It is always the frequency part that goes off. Must me some noise/interference . I will post again if I get this corrected after some googling.
Have you made it so that when it finds frequency, that is -all- the sketch is doing?
This is a quadratic equation.
Pressure = ACount^2 + BCount + C;
You may be able to replace it with a table lookup or by interpolating between table values.
The sketch I gave, did you try to have it calculate pressure and print that in the printout part?
Do you see how countFreq turns the counting on and off? Put the other parts but not the time-check code (any time-check code) inside of
if ( countFreq == 0 )
{
// here is where to check the other pin
}
You can have countFreq be more than just 0 or 1 and use that value to determine what code should run on any pass through loop(). But remember, loop() +must+ be fast or the time check and frequency count will be off.
With table lookup and using integer math you can greatly speed your calculating up.
The table would be kept in flash memory. With small code the table can be pretty big.
You see there are ways and there are ways. I learned to code when we could only dream of the speed of Arduino and had no FPU. Where I worked we had equivalent to 1 MHz AVR but more RAM (32k to 64k) and 360k floppy drives to run business on. But I was good with math before then and learned tricks to make it faster than human which for my needs was all that counted.
You, OTOH, need to keep up with signal frequency. You can do it but need to not do the other parts at the same time. If you have errors then, they can be tracked down and fixed as long as the principle formula does work.
