Read byte and time into EEPROM, then display with a comma between the time and the value?

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1

I have bytes of natural numbers 1-60 coming in at random times:

Example of send data

// Uno send

void setup() {
  Serial.begin(9600);
  
  int integersToSend[] = {1, 22, 30, 4, 50};
  for (int i = 0; i < 5; i++) 
  {
    Serial.print(integersToSend[i]);  // send as characters
    delay(1000);
  }
}

void loop() {}

I want to log the time (any time format) and what value was received into EEPROM:

#include <EEPROM.h>

const int timeRefreshDisplay = 30000;
const int EEPROM_SIZE = 100; // Define size of EEPROM available
int addr = 0; // EEPROM address pointer

unsigned long programStartTime;

void setup()
{
  Serial.begin(9600);
  Serial1.begin(9600); // Initialize Serial1 for data input
  programStartTime = millis(); // Record program start time
}

void loop()
{
  if (Serial1.available())
  {
    int receivedData = Serial1.read();

    if (receivedData != 0 && receivedData <= 60)
    {
      byte receivedValue = receivedData; // Convert?

      // Calculate the timestamp based on program start time
      unsigned long currentTime = programStartTime + millis();

      // Store the received timestamp and value in EEPROM
      EEPROM.put(addr, currentTime);
      addr += sizeof(unsigned long);
      EEPROM.put(addr, receivedValue);
      addr += sizeof(int);
    }
  }

  if (millis() - programStartTime >= timeRefreshDisplay)
  {
    programStartTime = millis();
    displayEEPROMData();
  }
}

void displayEEPROMData() {
  // Display all positions stored in EEPROM
  Serial.println("EEPROM:");

  for (int i = 0; i < EEPROM_SIZE; i += sizeof(unsigned long) + sizeof(int)) {
    if (i >= EEPROM_SIZE) {
      i = 0; // Start reading from the beginning when reaching the end of EEPROM
    }

    unsigned long timestamp;
    int value;
    EEPROM.get(i, timestamp);
    EEPROM.get(i + sizeof(unsigned long), value);

    // Display position data with timestamp in HH:MM:SS format
    Serial.print(String(i / (sizeof(unsigned long) + sizeof(int)) + 1) + ": ");
    Serial.println(String(timestamp) + ", " + String(value));
  }
}

Serial monitor

    EEPROM:
    1: 17330, 22272
    2: 101, 27943
    3: 4143972352, 116
    4: 0, 0
    5: 0, 0
    6: 0, 0
    7: 0, 0
    8: 0, 0
    9: 0, 0
    10: 0, 0
    11: 0, 0
    12: 0, 0
    13: 0, 0
    14: 0, 0
    15: 0, 0
    16: 0, 0
    17: 0, 0

I'm not quite sure how it is reading data into EEPROM. That has to be where the issue is. I just don't know how to fix it. I tried clearing out the memory:

    #include <EEPROM.h>
    
    
    void setup() {
       // initialize the LED pin as an output.
       pinMode(13, OUTPUT);
    
       for (int i = 0 ; i < 22; i++) /*EEPROM.length()*/ 
          EEPROM.write(i, 0);
    
       // turn the LED on when we're done
       digitalWrite(13, HIGH);
    }
    
    void loop() {}

Serial monitor again

EEPROM:
1: 0, 0
2: 0, 0
3: 0, 0
4: 0, 4
5: 70, 1
6: 22, 3
7: 230, 2
8: 182, 4
9: 134, 50
10: 234, 49
11: 209, 50
12: 213, 50
13: 185, 51
14: 189, 48
15: 161, 52
16: 137, 53
17: 140, 48

I'm using a Leonardo to receive. Budget is $20? I thought this was a simple thing, but struggling hard. Already sunk 22 hours into this.

2

You still don't use a delimiter.

"programStartTime" is always 0.

The only way this could possibly work would be a timeout after sending the last digit .- on the reiver you would try to find that timeout. But you don't do that, either. (Not to mention that would be a quite unstable aproach)

3

will send a varying number of characters. why not try coding that to send to Serial Monitor, and look at what you get, before routing it to another processor?

4

Because that is just a sample of data being sent. I don't get why everyone keeps trying to alter and the emulated/sample data.

That part works. It's storing/reading it into EEPROM that I'm having trouble with.

5

What do you think it does?

6

There is no delimiter in the actual data being sent. So I cannot add one to the sample data.

7

Because that's what I can see from reduced programs...

8

Nope, quite clearly set in setup(), and updated on display. Not the problem.

9

Not the problem, but you receive an int, "convert" it to a byte, then write it to EEPROM, and increment address by size of int. Try using sizeof() on the actual variables you're working with, to avoid a future nasty bug?

10

This probably should have been millis() - programStartTime.

11 
#include <EEPROM.h>

const int EEPROM_SIZE = 100; // Define size of EEPROM available
int addr = 0; // EEPROM address pointer

unsigned long programStartTime;

void setup()
{
  Serial.begin(9600);
  programStartTime = millis(); // Record program start time

  // Initialize EEPROM data
//  for (int i = 0; i < EEPROM_SIZE; i++) {
//    EEPROM.write(i, 0);
//  }
}

void loop()
{
  if (Serial.available())
  {
    int receivedData = Serial.read();

    if (receivedData >= 1 && receivedData <= 60)
    {
      byte receivedValue = static_cast<byte>(receivedData); // Convert to byte

      // Calculate the timestamp based on program start time
      unsigned long currentTime = millis() - programStartTime;

      // Store the received timestamp and value in EEPROM
      EEPROM.put(addr, currentTime);
      addr += sizeof(currentTime);
      EEPROM.put(addr, receivedValue);
      addr += sizeof(receivedValue);
    }
  }

  if (addr >= EEPROM_SIZE) {
    addr = 0; // Wrap around if the EEPROM is full
  }

}

void displayEEPROMData() {
  // Display all positions stored in EEPROM
  Serial.println("EEPROM:");

  for (int i = 0; i < EEPROM_SIZE; i += sizeof(unsigned long) + sizeof(byte)) {
    unsigned long timestamp;
    byte value;
    EEPROM.get(i, timestamp);
    EEPROM.get(i + sizeof(timestamp), value);

    // Display position data with timestamp in HH:MM:SS format
    Serial.print(String(i / (sizeof(unsigned long) + sizeof(byte)) + 1) + ": ");
    Serial.println(String(timestamp) + ", " + String(value));
  }
}
12

And? Same result?

13

With the displayEEPROMData() functions in there, I'm getting... well nothing now. Supposed to print out some initial EEPROM positions. Was spitting out zeros. Idk, I'm pretty burnt out.

#include <EEPROM.h>

const int EEPROM_SIZE = 100; // Define size of EEPROM available
int addr = 0; // EEPROM address pointer

unsigned long programStartTime;

void setup()
{
  Serial.begin(9600);
  programStartTime = millis(); // Record program start time

  // Initialize EEPROM data
  //  for (int i = 0; i < EEPROM_SIZE; i++) {
  //    EEPROM.write(i, 0);
  //  }
  displayEEPROMData();
}

void loop()
{
  if (Serial.available())
  {
    int receivedData = Serial.read();

    if (receivedData >= 1 && receivedData <= 60)
    {
      byte receivedValue = static_cast<byte>(receivedData); // Convert to byte

      // Calculate the timestamp based on program start time
      unsigned long currentTime = millis() - programStartTime;

      // Store the received timestamp and value in EEPROM
      EEPROM.put(addr, currentTime);
      addr += sizeof(currentTime);
      EEPROM.put(addr, receivedValue);
      addr += sizeof(receivedValue);

      displayEEPROMData();
    }
  }

  if (addr >= EEPROM_SIZE) {
    addr = 0; // Wrap around if the EEPROM is full
  }

}

void displayEEPROMData() {
  // Display all positions stored in EEPROM
  Serial.println("EEPROM:");

  for (int i = 0; i < EEPROM_SIZE; i += sizeof(unsigned long) + sizeof(byte)) {
    unsigned long timestamp;
    byte value;
    EEPROM.get(i, timestamp);
    EEPROM.get(i + sizeof(timestamp), value);

    // Display position data with timestamp in HH:MM:SS format
    Serial.print(String(i / (sizeof(unsigned long) + sizeof(byte)) + 1) + ": ");
    Serial.println(String(timestamp) + ", " + String(value));
  }
}
14

Added while (!Serial); after Serial.begin.

Serial monitor:

EEPROM:
1: 0, 0
2: 0, 0
3: 0, 0
4: 0, 0
5: 0, 0
6: 0, 0
7: 0, 0
8: 0, 0
9: 0, 0
10: 0, 0
11: 0, 0
12: 0, 0
13: 0, 0
14: 0, 0
15: 0, 0
16: 0, 0
17: 0, 0
18: 0, 0
19: 0, 0
20: 0, 0

15

Your last code works fine for me... I cleared the EEPROM. Then, each character sent is put in, with the timestamp before it. This is on a Nano, mind you, and the characters are coming from Serial Monitor, but that shouldn't matter.

EEPROM:
1: 5170, 52
2: 9186, 53
3: 20908, 54
4: 26445, 55
5: 0, 0
6: 0, 0
7: 0, 0
8: 0, 0
9: 0, 0
10: 0, 0
11: 0, 0
12: 0, 0
13: 0, 0
14: 0, 0
15: 0, 0
16: 0, 0
17: 0, 0
18: 0, 0
19: 0, 0
20: 0, 0

16

What times are those? Seems not right.

17

milliseconds since program start.

18

Whenever I send new data...

// Uno send

void setup() {
  Serial.begin(9600);
  
  int integersToSend[] = {1, 22, 30, 4, 50};
  for (int i = 0; i < 5; i++) 
  {
    Serial.write(integersToSend[i]);  // send as characters
    delay(1000);
  }
}

void loop() {}

The display on the receive program does not... happen.

19

image
image576×751 4.93 KB

Just stays with what was printed from setup.

20

You've got an Uno sending data, but Serial Monitor displaying - this is a Leondardo - one of the serial ports should be Serial1, no?
Guess I need to see how you've got things connected, then.
UnoSerial to?
Leonardo Serial to?
Leonardo Serial1 to?
Any software serial on top of this?

1 Like