EEPROM_writeAnything problem

Forum 2005-2010 (read only) Software Syntax & Programs
1

Hi,

I'have made a test file but when i run it it gives 2 lines on the LCD display

1024 (correct)
0 (not correct should be 1024)

I don't get the EEPROM_reedAnything working. Can anyone look at my code and please help me solve it.
I use Arduino 0019.

#include <EEPROM.h>
#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

template <class T> int EEPROM_writeAnything(int ee, const T& value)
{
    const byte* p = (const byte*)(const void*)&value;
    int i;
    for (i = 0; i < sizeof(value); i++)
        EEPROM.write(ee++, *p++);
    return i;
}


template <class T> int EEPROM_readAnything(int ee, T& value)
{
    byte* p = (byte*)(void*)&value;
    int i;
    for (i = 0; i < sizeof(value); i++)
        *p++ = EEPROM.read(ee++);
    return i;
}

long lengte;

struct config_t
{
    long lengte;
} cfg;

void setup(){

  lcd.begin(16, 2);
  lengte = 1024;
  EEPROM_writeAnything(0, cfg);
  delay(20);
    
  EEPROM_readAnything(0, cfg);
  delay(20);
  lcd.clear();
  lcd.print(lengte);
  lcd.setCursor(0,1);
  lcd.print(cfg.lengte);
  delay(500);
 
}

void loop(){

}
2

Did you mean

cfg.lengte = 1024;
  EEPROM_writeAnything(0, cfg);

or even

lengte = 1024;
  EEPROM_writeAnything(0, lengte);

?

3

Groove,

Thanks,

This one did the yob.

cfg.lengte = 1024;
EEPROM_writeAnything(0, cfg);

;D ;D ;D ;D ;D ;D

So i had to put cfg. before lengte when using it in the EEPROM_writeAnything.

4

In which case, your test proves nothing.
I think you need the second example.

5

Awol,

Tested the second one too and it works.

So, both codes are working but why is the second one the better one?

6

Think about the first case, and imagine that EEPROM_writeAnything works, but EEPROM_readAnything does not do anything

7

Okay, made 2 codes with both options mentioned above.
At the end there are 2 if statements, there is the diverence.

#include <EEPROM.h>
#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

const int analogInPin0 = 0;
const int analogInPin5 = 5;

int sensorValue0 = 0;    // value read from 5 pushputtons on analog 0
int sensorValue5 = 0;    // value read from the pot on analog 5
int outputValue = 0;     // 

long lengte;
long breedte;
long hoogte;

//---------------------
template <class T> int EEPROM_writeAnything(int ee, const T& value)
{
    const byte* p = (const byte*)(const void*)&value;
    int i;
    for (i = 0; i < sizeof(value); i++)
    EEPROM.write(ee++, *p++);
    return i;
}

template <class T> int EEPROM_readAnything(int ee, T& value)
{
    byte* p = (byte*)(void*)&value;
    int i;
    for (i = 0; i < sizeof(value); i++)
    *p++ = EEPROM.read(ee++);
    return i;
}
struct config_t
{
long lengte;
long breedte;
long hoogte;
} cfg;
//---------------------

void setup(){
 
  lcd.begin(16, 2);
}

void loop(){
  
 
  sensorValue0 = analogRead(analogInPin0);
  sensorValue5 = analogRead(analogInPin5);
  outputValue = map(sensorValue0, 0, 1023, 0, 255);
  
  
  lcd.setCursor(0,0);
  lcd.print("Sensor=       cm");
  lcd.setCursor(8,0);
  lcd.print(sensorValue5);
  
  EEPROM_readAnything(0, cfg);
  lcd.setCursor(0,1);
  lcd.print("L=   cm B=   cm");
  lcd.setCursor(2,1);
  lcd.print(cfg.lengte);
  lcd.setCursor(9,1);
  lcd.print(cfg.breedte);
 
  if (outputValue == 184){
     cfg.lengte = sensorValue5;
     EEPROM_writeAnything(0, cfg);
     delay (100);
     }
  if (outputValue == 0){
     cfg.breedte = sensorValue5;
     EEPROM_writeAnything(0, cfg);
     delay (100);
     }
  delay(20);
}

#include <EEPROM.h>
#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

const int analogInPin0 = 0;
const int analogInPin5 = 5;

int sensorValue0 = 0;    // value read from 5 pushputtons on analog 0
int sensorValue5 = 0;    // value read from the pot on analog 5
int outputValue = 0;     // 

long lengte;
long breedte;
long hoogte;

//---------------------
template <class T> int EEPROM_writeAnything(int ee, const T& value)
{
    const byte* p = (const byte*)(const void*)&value;
    int i;
    for (i = 0; i < sizeof(value); i++)
    EEPROM.write(ee++, *p++);
    return i;
}

template <class T> int EEPROM_readAnything(int ee, T& value)
{
    byte* p = (byte*)(void*)&value;
    int i;
    for (i = 0; i < sizeof(value); i++)
    *p++ = EEPROM.read(ee++);
    return i;
}
struct config_t
{
long lengte;
long breedte;
long hoogte;
} cfg;
//---------------------

void setup(){
 
  lcd.begin(16, 2);
}

void loop(){
  
 
  sensorValue0 = analogRead(analogInPin0);
  sensorValue5 = analogRead(analogInPin5);
  outputValue = map(sensorValue0, 0, 1023, 0, 255);
  
  
  lcd.setCursor(0,0);
  lcd.print("Sensor=       cm");
  lcd.setCursor(8,0);
  lcd.print(sensorValue5);
  
  EEPROM_readAnything(0, cfg);
  lcd.setCursor(0,1);
  lcd.print("L=   cm B=   cm");
  lcd.setCursor(2,1);
  lcd.print(cfg.lengte);
  lcd.setCursor(9,1);
  lcd.print(cfg.breedte);
 
  if (outputValue == 184){
     lengte = sensorValue5;
     EEPROM_writeAnything(0, lengte);
     delay (100);
     }
  if (outputValue == 0){
     breedte = sensorValue5;
     EEPROM_writeAnything(0, breedte);
     delay (100);
     }
  delay(20);
}

Both codes are working.

But i can't figure out why "EEPROM_readAnything does not do anything" in the first code.

8

I said "imagine" it does nothing - I didn't say that it didn't work.
I was trying to make the point that when you're testing something, use a method that makes the result as unambiguous as possible.

If you write a value out from a variable, reading back into the same variable may not prove anything, if the "read" isn't doing anything at all - the initial write would be non-destructive, so the variable would still contain the value you were expecting to see.
Either zero or invert the value before reading back, or read into a different variable.