Reading external EEPROM address Strange Results - SOLVED

Projects Programming
1

Hello I'm trying to read a External eeprom chip for it's address. It is a 24c02w6 chip that is a on a Dell PCB used for a Raid key. I'm not trying to copy whatever is on it. I'm trying to see If i can reuse it for other things. It has a 2k eeprom. I thought it would be good for something. Below is the Results of what the i2c scanner came up with. and Also images of the device. I have no other device on the i2c or attached to my arduino. Can someone help me to figure this out please?

I2C Scanner
Scanning...
I2C device found at address 0x01  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x58  !
I2C device found at address 0x59  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x2E  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x38  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x37  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x35  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x02  !
I2C device found at address 0x6B  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x27  !
I2C device found at address 0x70  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x60  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x2C  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x57  !
I2C device found at address 0x58  !
I2C device found at address 0x59  !
I2C device found at address 0x5A  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x2E  !
done

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x02  !
I2C device found at address 0x03  !
I2C device found at address 0x04  !
done

Scanning...
I2C device found at address 0x01  !
done

Scanning...
No I2C devices found

Scanning...
I2C device found at address 0x01  !
I2C device found at address 0x02  !
I2C device found at address 0x03  !
I2C device found at address 0x04  !
I2C device found at address 0x05  !
I2C device found at address 0x06  !
I2C device found at address 0x07  !
I2C device found at address 0x08  !
I2C device found at address 0x09  !
I2C device found at address 0x0A  !
I2C device found at address 0x0B  !
I2C device found at address 0x0C  !
I2C device found at address 0x0D  !
I2C device found at address 0x0E  !
I2C device found at address 0x0F  !
I2C device found at address 0x10  !
I2C device found at address 0x11  !
I2C device found at address 0x12  !
I2C device found at address 0x13  !
I2C device found at address 0x14  !
I2C device found at address 0x15  !
I2C device found at address 0x16  !
I2C device found at address 0x17  !
I2C device found at address 0x18  !
I2C device found at address 0x19  !
I2C device found at address 0x1A  !
I2C device found at address 0x1B  !
I2C device found at address 0x1C  !
I2C device found at address 0x1D  !
I2C device found at address 0x1E  !
I2C device found at address 0x1F  !

IMG-1479
IMG-14791920×2560 461 KB

IMG-1480
IMG-14801920×2560 776 KB

Joseph

2

I think the I2C address of the ST Micro 24C02W6 should be 0x50 through 0x57 depending on how you set the Enable pins.

Pin 1: E0
Pin 2: E1
Pin 3: E2
Pin 4: Vss (Ground)

Pin 8: Vcc (+5V)
Pin 7: WC (Write Control)
Pin 6: SCL
Pin 5: SDA

How are the pins hooked up?

3

Hello John, From What I read on the site The pinout is Pin 1 is Vcc; pins 7 and 9 are ground. Pin 4 is Scl and Pin 8 is SDA They said. This Is the only thing I can find online. And they did a great job tracking down the pins with all the resisters ands capacitors on it. As far as the enable pin. Noting on it. I need to see that myself because There is no marking to indicate whick is pin one.

Joseph

4

Looks like that board sets the I2C address to 0x54: E0 and E1 connected to ground and E2 connected to Vcc (+5V).

5

Its not a complex board, you could easily worh out how its all connected with a multimeter.

6

Hello Weber, yea I’m doing that. I’m not home at the moment to do it. I’m dealing with my wife mother stuff at her place. She recently passed. But tonight my time I will try it thank you.

Joseph

M

7

Thank you John. I will try it later my time at night when I get home.

Joseph

8

Hello, This is just a update to what I believe is the pinout so far.

8286r-dimensions
8286r-dimensions721×535 12.2 KB

8286r-schematic

Not sure this is correct or I'm midding something on the first image. I put red color for the pinout.

Joseph

9

Hi @josephchrzempiec
To use an I2C BUS you need it to have pullup resistors.
FFrom what I see by the schematic shown that the board does not have these resistors, so it will be necessary to put the SDL and SCA.
Try 4K7 resistors.

RV mineirin

10

The Arduino have internal pull-up resistors.
Well. Uno, Leonardo, Micro, Pro Micro, Mega, Zero and the SDA0 on the Due all have pull-up resistors. Only the SDA1 on the Due do not.
And this is more apparent that the SDA1 on the Due use I think the "wire1" library

I2C device found at address 0x02  !
I2C device found at address 0x03  !
I2C device found at address 0x04  !
I2C device found at address 0x05  !
I2C device found at address 0x06  !
I2C device found at address 0x07  !
I2C device found at address 0x08  !
I2C device found at address 0x09  !
I2C device found at address 0x0A  !
I2C device found at address 0x0B  !
I2C device found at address 0x0C  !
I2C device found at address 0x0D  !
I2C device found at address 0x0E  !
I2C device found at address 0x0F  !
I2C device found at address 0x10  !
I2C device found at address 0x11  !
I2C device found at address 0x12  !
I2C device found at address 0x13  !
I2C device found at address 0x14  !
I2C device found at address 0x15  !
I2C device found at address 0x16  !
I2C device found at address 0x17  !
I2C device found at address 0x18  !
I2C device found at address 0x19  !
I2C device found at address 0x1A  !
I2C device found at address 0x1B  !
I2C device found at address 0x1C  !
I2C device found at address 0x1D  !
I2C device found at address 0x1E  !
I2C device found at address 0x1F  !

@josephchrzempiec
this look broken.

I had tried to find a datasheet for it but couldn't find one. You would want one to know the expected behavior (e.g. what commands you need to send to read info, in what format, and what command is needed to write to the chip and stuff. Perhaps the chip is dead, for some reason. Like a power surge or something that took it out.

Lastly.
I2C is a protocol designed for on-board chip communication. Make your wires as short as possible (total length < 20cm)

11

Hello, I'm using the adafruit Samd51 Grand Centeral board. It is currently the only board I have at the moment.

Joseph

12

Hi @cdr_xavier @josephchrzempiec
The values of the internal pull-up resistors are too high and therefore not within the I2C protocol recommendation.
Read :
"The value of Arduino (ATmega328P) internal pull-up resistors.
The inbuilt pull-up resistors on the Arduino/AVR outputs aren't well defined. When these are used, the exact value rarely matters - the datasheet gives a pretty wide range: 20kOhm-50kOhm.

There is a discussion on the official Arduino forum here, with a pull-up measured as R=30.9K from an effective voltage of 4.58V (which is different to the supply voltage). In short I measured the value on one chip as 34k from 4.6V, it will vary from chip to chip and even with temperature."

Ref: Little Projects: The value of Arduino (ATmega328P) internal pull-up resistors.

I2C Bus Pullup Resistor Calculation - TI E2E - Texas Instruments

RV mineirin

13

I got it to work. Address of 0x54. I'm now tring to read the whole eeprom. Well trying to attemp it next. Thank you

Joseph

14

Intriguing. Maybe that's why my environment sensor cluster failed to work.

15

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.