24AA256 I2C EEprom

[AndrewB]

Has anyone used this 24AA256 IC?

I'm using the DS1307 memory locations at the moment and would like to change this due to the battery.

Is there another way to save data other than a SD card?

[David John Barker]

Have you take a look at some I2C modules

[David John Barker]

I'll try and dig some out - I posted an SPI module by mistake - oops

[AndrewB]

Thanks David.

Will look at that.

[David John Barker]

This might be better. I have not used the device you mentioned, but this works for a 24LC128

Code: Select all

Imports I2C

Sub Main()
   Const I2C_EEPROM As Byte = &HA0  ' target 24LC128 I2C EEPROM device...
   Dim Value As Byte                ' Value that is read back from device
   Dim Address As UShort = 0        ' EEPROM address

   ' initialise the I2C module...
   I2C.Initialize()

   ' write some data...
   I2C.Start()                         
   I2C.WriteByte(I2C_EEPROM)             
   I2C.WriteByte(Address.Byte1)       
   I2C.WriteByte(Address.Byte0)       
   I2C.WriteByte("X")                 
   I2C.Stop()

   ' allow external EEPROM to write data...
   DelayMS(10)

   ' read the data back...
   I2C.Start()
   I2C.WriteByte(I2C_EEPROM)
   I2C.WriteByte(Address.Byte1)       
   I2C.WriteByte(Address.Byte0)       
   I2C.Restart()                         
   I2C.WriteByte(I2C_EEPROM + 1)
   Value = I2C.ReadByte()
   I2C.Acknowledge(IsNotAcknowledge)
   I2C.Stop()

   ' output the result
   Console.WriteLine("Value = ", Value)
End Sub

[AndrewB]

Thanks