How to store data in TM4C

[lilyhack 3]

I am building a control system (TM4C129/123) that generates many data. These data are sent back to a higher level controller (Raspberry Pi) through ZigBee.

 

Now, instead of TI always sending the data, I want to change the system so that when Raspberry Pi request data, only then TI sends data. So that means storing those data until the data request come. The data can be lost after the power off. 

 

How do I do that? I understand there is a limit to how long we can store the data depending on the size of the data. 

[PTB 27]

You could also use some kind of external storage.

 

If the data isn't too much you could store in an external eeprom chip. I2c or spi. Alternatively you could use an sd card.

[L.R.A 78]

You can use internal EEPROM or the flash.

The TM4C1294 should have more than enough flash, and the tm4c123 should be enough depending on your code size and data size.

[lilyhack 3]

Do you have an example of how to read/write to the internal EEPROM?

[L.R.A 78]

Note that the EEPROM is kinda small compared to the flash.

The TM4C123 has 2KB and the TM4C1294 has 6KB.

You access it in blocks of 16 word.

There is probably a example in Tivaware.

Here is how I enable it:
 

	bool eeprom_good = false;
	if(!SysCtlPeripheralReady(SYSCTL_PERIPH_EEPROM0))
	{
		SysCtlPeripheralEnable(SYSCTL_PERIPH_EEPROM0);
		while(!(SysCtlPeripheralReady(SYSCTL_PERIPH_EEPROM0)));
	}
	if(EEPROMInit() == EEPROM_INIT_OK)
	{
		eeprom_good = true;
	}
	return(eeprom_good);

How I read it:
 

	uint32_t temp;
	EEPROMRead(&temp, address, 4);
	return temp;

And how I write into it:
 

	uint32_t	temp;
	uint32_t	result;
	temp = value;
	result = EEPROMProgram(&temp,address,4);
	return(result);

[L.R.A 78]

Check Tivaware manual on what the functions  EEPROMRead and EEPROMProgram take as parameter 

[L.R.A 78]

btw, using the flash should be easy.

The problem is you have to erase an entire block to write it.
The TM4C123 has blocks 1KB and the TM4C1294 is of 16KB. 

So you can for example simply erase an entire block and then write 1 word (or just byte? I don't remember how specific you can write) as data arrives. Since you erased the entire block you can do that.
Problem is, if you want to go back and start over the block, or change a value, you have to erase the entire block! Just be aware if you end up using flash