Hi Cattledog,
Thanks for getting back to me. That did the trick. Also implemented another change to add to decimal places. I am ready to put my project to the test but have one little glitch. When i power up the mega board using the usb serial cable it works great. I tried removing the cable and using a 12v / 1amp power adapter but it doesn't work as expected. It powers up okay and I see the Contact Points: string on the Lcd, but the number digits seem to appear behind the Contact Points: string on the same line, and it doesn't look as if the output of the encoder is being read. i assume that I have hooked something up incorrectly. Any ideas?
Bill
#include <SD.h>
#include <SPI.h>
#include <LiquidCrystal.h>
#define MAX_ENCODER_VALUE 4095
const int chipSelect = 53;
const int8_t encoderDirections[] = {0, -1, 1, 0, 1, 0, 0, -1, -1, 0, 0, 1, 0, 1, -1, 0};
volatile int16_t counter = 0;
volatile int8_t direction = 0;
byte Flag = 1;//add flag to control multiple records for same button press
const int numRows = 2;
const int numCols = 16;
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
String result;
// define some values used by the panel and buttons
int lcd_key = 0;
int adc_key_in = 0;
#define btnRIGHT 0
#define btnUP 1
#define btnRESULT 2
#define btnLEFT 3
#define btnSELECT 4
#define btnNONE 5
int read_LCD_buttons()
{
adc_key_in = analogRead(0); // read the value from the sensor
if (adc_key_in < 50) return btnRIGHT;
if (adc_key_in < 195) return btnUP;
if (adc_key_in < 380) return btnRESULT;
if (adc_key_in < 555) return btnLEFT;
if (adc_key_in < 790) return btnSELECT;
if (adc_key_in < 1024) return btnNONE;//add
}
void setup() {
Serial.begin(9600);
Serial.println("Initializing SD card...");
pinMode(chipSelect, OUTPUT);//set chip select PIN as 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.");
pinMode(18, INPUT_PULLUP);
pinMode(19, INPUT_PULLUP);
// set up the LCD's number of columns and rows:
lcd.begin(numCols, numRows);
attachInterrupt(4, encoder_interrupt, CHANGE);
attachInterrupt(5, encoder_interrupt, CHANGE);
}
void loop() {
// make a string for assembling the data to log:
String dataString = "";
lcd_key = read_LCD_buttons(); // read the buttons
switch (lcd_key) // depending on which button was pushed, we perform an action
{
case btnRIGHT:
if (Flag == 0)
{
dataString = String("RCP \t") + String(mapfloat(getCount(), 0, MAX_ENCODER_VALUE, 0, 99));
File dataFile = SD.open("dataRCP.txt", FILE_WRITE);//open a file named dataRCP.txt.
if (dataFile) { // if the file is available, write to it ('datafile' is returned 1 if SD.open was successful.
dataFile.println(dataString);//print the concatenated data string and finish the line with a carriage return (println adds the CR automatically after printing the string)
dataFile.close(); //close the file. IT is a good idea to always open/close a file before and after writing to it. That way, if someone removes the card the file is most
//likely o.k. and can be read with the computer.
// Serial.println(dataString);// print the string also to the serial port, so we can see what is going on.
}
// if SD.open is not successful it returns a 0, i.e. the else{} is executed if the file could not be opened/created successfully.
else {
Serial.println("error opening dataRCP.txt");//in that case print an error message
}
Flag = 1;
}
break;
case btnLEFT:
if (Flag == 0)
{
dataString = String("LCP \t") + String(mapfloat(getCount(), 0, MAX_ENCODER_VALUE, 0, 99));
File dataFile = SD.open("dataLCP.txt", FILE_WRITE);//open a file named dataLCP.txt.
if (dataFile) { // if the file is available, write to it ('datafile' is returned 1 if SD.open was successful.
dataFile.println(dataString);//print the concatenated data string and finish the line with a carriage return (println adds the CR automatically after printing the string)
dataFile.close(); //close the file. IT is a good idea to always open/close a file before and after writing to it. That way, if someone removes the card the file is most
//likely o.k. and can be read with the computer.
Serial.println(dataString);// print the string also to the serial port, so we can see what is going on.
}
// if SD.open is not successful it returns a 0, i.e. the else{} is executed if the file could not be opened/created successfully.
else {
Serial.println("error opening dataLCP.txt");//in that case print an error message
}
Flag = 1;
}
break;
case btnRESULT:
break;
case btnNONE:
Flag = 0;
break;
}//closes switch
lcd.setCursor(0, 0);
lcd.print("Contact Points: ");
lcd.setCursor(0, 1);
float value = mapfloat(getCount(), 0, MAX_ENCODER_VALUE, 0, 99);
if (value <10)
lcd.print("0");
lcd.print(value);
}//closes loop
void encoder_interrupt() {
static uint8_t oldEncoderState = 0;
oldEncoderState <<= 2;
oldEncoderState |= ((PIND >> 2) & 0x03);
direction = encoderDirections[(oldEncoderState & 0x0F)];
counter += direction;
if (counter < 0) counter = MAX_ENCODER_VALUE;
else if (counter > MAX_ENCODER_VALUE) counter = 0;
}
float mapfloat(long x, long in_min, long in_max, long out_min, long out_max)
{
return float((x - in_min) * float((out_max - out_min)) / (in_max - in_min) + out_min);
}
int getCount ()
{
noInterrupts();
int copyCounter = counter;
interrupts();
return copyCounter;
}