Meadow.Foundation.ICs.EEPROM.At24Cxx

At24Cxx
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

The AT24Cxx series of chips provide a mechanism for storing data that will survive a power outage or battery failure. These EEPROMs are available in varying sizes and are accessible using the I2C interface.

Code Example

At24Cxx eeprom;

public override Task Initialize()
{
    Resolver.Log.Info("Initialize...");

    //256kbit = 256*1024 bits = 262144 bits = 262144 / 8 bytes = 32768 bytes
    //if you're using the ZS-042 board, it has an AT24C32 and uses the default value of 8192
    eeprom = new At24Cxx(i2cBus: Device.CreateI2cBus(), memorySize: 32768);

    return base.Initialize();
}

public override Task Run()
{
    Resolver.Log.Info("Write to eeprom");
    eeprom.Write(0, new byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 });

    Resolver.Log.Info("Read from eeprom");
    var memory = eeprom.Read(0, 16);

    for (ushort index = 0; index < 16; index++)
    {
        Thread.Sleep(50);
        Resolver.Log.Info("Byte: " + index + ", Value: " + memory[index]);
    }

    eeprom.Write(3, new byte[] { 10 });
    eeprom.Write(7, new byte[] { 1, 2, 3, 4 });
    memory = eeprom.Read(0, 16);

    for (ushort index = 0; index < 16; index++)
    {
        Thread.Sleep(50);
        Resolver.Log.Info("Byte: " + index + ", Value: " + memory[index]);
    }

    return base.Run();
}

Sample project(s) available on GitHub

Wiring Example

To wire a At24Cxx to your Meadow board, connect the following:

At24Cxx	Meadow Pin
GND	GND
SCL	D08 (SCL)
SDA	D07 (SDA)
VCC	3V3

It should look like the following diagram: