Hi, My friend,
I want to save data from Arduino to SD card,
I've used EDB master library but I have a lot of problems.
For example :
if I updated one value, its changed in all tables
please, what's the best way to save data in SD card without problems?
Thanks 
Let's see an example of your code that causes the problem. What are these tables to which you refer ?
Hi, my friends,
what's the best way to save the values to SD card?
Thanks
Have you got any SD libraries installed ?
Have you looked at the examples in the IDE ?
What sort of data do you want to save ?
UKHeliBob:
Have you got any SD libraries installed ?
Have you looked at the examples in the IDE ?
What sort of data do you want to save ?
#include "Arduino.h"
#include <EDB.h>
// Use the external SPI SD card as storage
#include <SPI.h>
#include <SD.h>
#define SD_PIN 10 // SD Card CS pin
#define TABLE_SIZE 8192
// The number of demo records that should be created. This should be less
// than (TABLE_SIZE - sizeof(EDB_Header)) / sizeof(LogEvent). If it is higher,
// operations will return EDB_OUT_OF_RANGE for all records outside the usable range.
#define RECORDS_TO_CREATE 10
char* db_name = "/db/edb_test.db";
File dbFile;
// Arbitrary record definition for this table.
// This should be modified to reflect your record needs.
struct LogEvent {
int id;
int temperature;
}
logEvent;
// The read and write handlers for using the SD Library
// Also blinks the led while writing/reading
void writer (unsigned long address, byte data) {
digitalWrite(13, HIGH);
dbFile.seek(address);
dbFile.write(data);
dbFile.flush();
digitalWrite(13, LOW);
}
byte reader (unsigned long address) {
digitalWrite(13, HIGH);
dbFile.seek(address);
byte b = dbFile.read();
digitalWrite(13, LOW);
return b;
}
// Create an EDB object with the appropriate write and read handlers
EDB db(&writer, &reader);
// Run the demo
void setup()
{
pinMode(13, OUTPUT);
digitalWrite(13, LOW);
Serial.begin(9600);
Serial.println(" Extended Database Library + External SD CARD storage demo");
Serial.println();
randomSeed(analogRead(0));
if (!SD.begin(SD_PIN)) {
Serial.println("No SD-card.");
return;
}
// Check dir for db files
if (!SD.exists("/db")) {
Serial.println("Dir for Db files does not exist, creating...");
SD.mkdir("/db");
}
if (SD.exists(db_name)) {
dbFile = SD.open(db_name, FILE_WRITE);
// Sometimes it wont open at first attempt, espessialy after cold start
// Let's try one more time
if (!dbFile) {
dbFile = SD.open(db_name, FILE_WRITE);
}
if (dbFile) {
Serial.print("Openning current table... ");
EDB_Status result = db.open(0);
if (result == EDB_OK) {
Serial.println("DONE");
} else {
Serial.println("ERROR");
Serial.println("Did not find database in the file " + String(db_name));
Serial.print("Creating new table... ");
db.create(0, TABLE_SIZE, (unsigned int)sizeof(logEvent));
Serial.println("DONE");
return;
}
} else {
Serial.println("Could not open file " + String(db_name));
return;
}
} else {
Serial.print("Creating table... ");
// create table at with starting address 0
dbFile = SD.open(db_name, FILE_WRITE);
db.create(0, TABLE_SIZE, (unsigned int)sizeof(logEvent));
Serial.println("DONE");
}
recordLimit();
countRecords();
createRecords(RECORDS_TO_CREATE);
countRecords();
selectAll();
deleteOneRecord(RECORDS_TO_CREATE / 2);
countRecords();
selectAll();
appendOneRecord(RECORDS_TO_CREATE + 1);
countRecords();
selectAll();
insertOneRecord(RECORDS_TO_CREATE / 2);
countRecords();
selectAll();
updateOneRecord(RECORDS_TO_CREATE);
selectAll();
countRecords();
deleteAll();
Serial.println("Use insertRec() and deleteRec() carefully, they can be slow");
countRecords();
for (int i = 1; i <= 20; i++) insertOneRecord(1); // inserting from the beginning gets slower and slower
countRecords();
for (int i = 1; i <= 20; i++) deleteOneRecord(1); // deleting records from the beginning is slower than from the end
countRecords();
dbFile.close();
}
void loop()
{
}
// utility functions
void recordLimit()
{
Serial.print("Record Limit: ");
Serial.println(db.limit());
}
void deleteOneRecord(int recno)
{
Serial.print("Deleting recno: ");
Serial.println(recno);
db.deleteRec(recno);
}
void deleteAll()
{
Serial.print("Truncating table... ");
db.clear();
Serial.println("DONE");
}
void countRecords()
{
Serial.print("Record Count: ");
Serial.println(db.count());
}
void createRecords(int num_recs)
{
Serial.print("Creating Records... ");
for (int recno = 1; recno <= num_recs; recno++)
{
logEvent.id = recno;
logEvent.temperature = random(1, 125);
EDB_Status result = db.appendRec(EDB_REC logEvent);
if (result != EDB_OK) printError(result);
}
Serial.println("DONE");
}
void selectAll()
{
for (int recno = 1; recno <= db.count(); recno++)
{
EDB_Status result = db.readRec(recno, EDB_REC logEvent);
if (result == EDB_OK)
{
Serial.print("Recno: ");
Serial.print(recno);
Serial.print(" ID: ");
Serial.print(logEvent.id);
Serial.print(" Temp: ");
Serial.println(logEvent.temperature);
}
else printError(result);
}
}
void updateOneRecord(int recno)
{
Serial.print("Updating record at recno: ");
Serial.print(recno);
Serial.print("... ");
logEvent.id = 1234;
logEvent.temperature = 4321;
EDB_Status result = db.updateRec(recno, EDB_REC logEvent);
if (result != EDB_OK) printError(result);
Serial.println("DONE");
}
void insertOneRecord(int recno)
{
Serial.print("Inserting record at recno: ");
Serial.print(recno);
Serial.print("... ");
logEvent.id = recno;
logEvent.temperature = random(1, 125);
EDB_Status result = db.insertRec(recno, EDB_REC logEvent);
if (result != EDB_OK) printError(result);
Serial.println("DONE");
}
void appendOneRecord(int id)
{
Serial.print("Appending record... ");
logEvent.id = id;
logEvent.temperature = random(1, 125);
EDB_Status result = db.appendRec(EDB_REC logEvent);
if (result != EDB_OK) printError(result);
Serial.println("DONE");
}
void printError(EDB_Status err)
{
Serial.print("ERROR: ");
switch (err)
{
case EDB_OUT_OF_RANGE:
Serial.println("Recno out of range");
break;
case EDB_TABLE_FULL:
Serial.println("Table full");
break;
case EDB_OK:
default:
Serial.println("OK");
break;
}
}
I used this code but I can't save data in two table ??
Hi My friends
I use this library EDB master
I want to save my data into 3 different tables
what's the best way to do this?
#include "Arduino.h"
#include <EDB.h>
// Use the external SPI SD card as storage
#include <SPI.h>
#include <SD.h>
#define SD_PIN 10Â // SD Card CS pin
#define TABLE_SIZE 8192
// The number of demo records that should be created. This should be less
// than (TABLE_SIZE - sizeof(EDB_Header)) / sizeof(LogEvent). If it is higher,
// operations will return EDB_OUT_OF_RANGE for all records outside the usable range.
#define RECORDS_TO_CREATE 10
char* db_name = "/db/edb_test.db";
File dbFile;
// Arbitrary record definition for this table.
// This should be modified to reflect your record needs.
struct LogEvent {
  int id;
  int temperature;
}
logEvent;
// The read and write handlers for using the SD Library
// Also blinks the led while writing/reading
void writer (unsigned long address, byte data) {
  digitalWrite(13, HIGH);
  dbFile.seek(address);
  dbFile.write(data);
  dbFile.flush();
  digitalWrite(13, LOW);
}
byte reader (unsigned long address) {
  digitalWrite(13, HIGH);
  dbFile.seek(address);
  byte b = dbFile.read();
  digitalWrite(13, LOW);
  return b;
}
// Create an EDB object with the appropriate write and read handlers
EDB db(&writer, &reader);
// Run the demo
void setup()
{
  pinMode(13, OUTPUT);
  digitalWrite(13, LOW);
  Serial.begin(9600);
  Serial.println(" Extended Database Library + External SD CARD storage demo");
  Serial.println();
  randomSeed(analogRead(0));
  if (!SD.begin(SD_PIN)) {
    Serial.println("No SD-card.");
    return;
  }
  // Check dir for db files
  if (!SD.exists("/db")) {
    Serial.println("Dir for Db files does not exist, creating...");
    SD.mkdir("/db");
  }
  if (SD.exists(db_name)) {
    dbFile = SD.open(db_name, FILE_WRITE);
    // Sometimes it wont open at first attempt, espessialy after cold start
    // Let's try one more time
    if (!dbFile) {
      dbFile = SD.open(db_name, FILE_WRITE);
    }
    if (dbFile) {
      Serial.print("Openning current table... ");
      EDB_Status result = db.open(0);
      if (result == EDB_OK) {
        Serial.println("DONE");
      } else {
        Serial.println("ERROR");
        Serial.println("Did not find database in the file " + String(db_name));
        Serial.print("Creating new table... ");
        db.create(0, TABLE_SIZE, (unsigned int)sizeof(logEvent));
        Serial.println("DONE");
        return;
      }
    } else {
      Serial.println("Could not open file " + String(db_name));
      return;
    }
  } else {
    Serial.print("Creating table... ");
    // create table at with starting address 0
    dbFile = SD.open(db_name, FILE_WRITE);
    db.create(0, TABLE_SIZE, (unsigned int)sizeof(logEvent));
    Serial.println("DONE");
  }
  recordLimit();
  countRecords();
  createRecords(RECORDS_TO_CREATE);
  countRecords();
  selectAll();
  deleteOneRecord(RECORDS_TO_CREATE / 2);
  countRecords();
  selectAll();
  appendOneRecord(RECORDS_TO_CREATE + 1);
  countRecords();
  selectAll();
  insertOneRecord(RECORDS_TO_CREATE / 2);
  countRecords();
  selectAll();
  updateOneRecord(RECORDS_TO_CREATE);
  selectAll();
  countRecords();
  deleteAll();
  Serial.println("Use insertRec() and deleteRec() carefully, they can be slow");
  countRecords();
  for (int i = 1; i <= 20; i++) insertOneRecord(1); // inserting from the beginning gets slower and slower
  countRecords();
  for (int i = 1; i <= 20; i++) deleteOneRecord(1); // deleting records from the beginning is slower than from the end
  countRecords();
  dbFile.close();
}
void loop()
{
}
// utility functions
void recordLimit()
{
  Serial.print("Record Limit: ");
  Serial.println(db.limit());
}
void deleteOneRecord(int recno)
{
  Serial.print("Deleting recno: ");
  Serial.println(recno);
  db.deleteRec(recno);
}
void deleteAll()
{
  Serial.print("Truncating table... ");
  db.clear();
  Serial.println("DONE");
}
void countRecords()
{
  Serial.print("Record Count: ");
  Serial.println(db.count());
}
void createRecords(int num_recs)
{
  Serial.print("Creating Records... ");
  for (int recno = 1; recno <= num_recs; recno++)
  {
    logEvent.id = recno;
    logEvent.temperature = random(1, 125);
    EDB_Status result = db.appendRec(EDB_REC logEvent);
    if (result != EDB_OK) printError(result);
  }
  Serial.println("DONE");
}
void selectAll()
{
  for (int recno = 1; recno <= db.count(); recno++)
  {
    EDB_Status result = db.readRec(recno, EDB_REC logEvent);
    if (result == EDB_OK)
    {
      Serial.print("Recno: ");
      Serial.print(recno);
      Serial.print(" ID: ");
      Serial.print(logEvent.id);
      Serial.print(" Temp: ");
      Serial.println(logEvent.temperature);
    }
    else printError(result);
  }
}
void updateOneRecord(int recno)
{
  Serial.print("Updating record at recno: ");
  Serial.print(recno);
  Serial.print("... ");
  logEvent.id = 1234;
  logEvent.temperature = 4321;
  EDB_Status result = db.updateRec(recno, EDB_REC logEvent);
  if (result != EDB_OK) printError(result);
  Serial.println("DONE");
}
void insertOneRecord(int recno)
{
  Serial.print("Inserting record at recno: ");
  Serial.print(recno);
  Serial.print("... ");
  logEvent.id = recno;
  logEvent.temperature = random(1, 125);
  EDB_Status result = db.insertRec(recno, EDB_REC logEvent);
  if (result != EDB_OK) printError(result);
  Serial.println("DONE");
}
void appendOneRecord(int id)
{
  Serial.print("Appending record... ");
  logEvent.id = id;
  logEvent.temperature = random(1, 125);
  EDB_Status result = db.appendRec(EDB_REC logEvent);
  if (result != EDB_OK) printError(result);
  Serial.println("DONE");
}
void printError(EDB_Status err)
{
  Serial.print("ERROR: ");
  switch (err)
  {
    case EDB_OUT_OF_RANGE:
      Serial.println("Recno out of range");
      break;
    case EDB_TABLE_FULL:
      Serial.println("Table full");
      break;
    case EDB_OK:
    default:
      Serial.println("OK");
      break;
  }
}
Thanks !!
I can't save data in two table ??
What happens when you try ?
What should happen ?
If you want 3 different tables, you will most likely need 3 different filenames on you SD card and 3 different EDB objects and, if the records are different, 3 different sets of reader/writer handlers.
What have you tried so far? It looks like you just posted the demo code without modification.
blh64:
If you want 3 different tables, you will most likely need 3 different filenames on you SD card and 3 different EDB objects and, if the records are different, 3 different sets of reader/writer handlers.What have you tried so far? It looks like you just posted the demo code without modification.
I added new EDB and New Table
like this
db.create(0, TABLE_SIZE, (unsigned int)sizeof(logEvent));
db.create(1, TABLE_SIZE, (unsigned int)sizeof(logEvent2));
UKHeliBob:
What happens when you try ?
What should happen ?
when I update the value in table 1 it will update in table 2
I want to separate table 1 and table 2
when I update the value in table 1 it will update in table 2
I want to separate table 1 and table 2
Are you sure that you can have more than one table each database file ?
The create method doesn't create a database, it writes the header, you call it once for any given EDB object
from what I see - look at the source code of the library (its not very well commented alas)...
You need to declare 3 EDB objects, each with separate writers and readers using 3 different files.
On the Uno there is not enough RAM to open 3 files at once on an SDcard I fear though...
MarkT:
The create method doesn't create a database, it writes the header, you call it once for any given EDB object
from what I see - look at the source code of the library (its not very well commented alas)...You need to declare 3 EDB objects, each with separate writers and readers using 3 different files.
On the Uno there is not enough RAM to open 3 files at once on an SDcard I fear though...
do u know another way to save data?
do u know another way to save data?
Do you need all 3 files to be open at once ?
Can you please summarise what you are trying to do ?