ATXmega EEPROM problem

techknight · Joined: 21 Apr 2008 Posts: 231

I am having a very hard time saving to EEPROM, if I have a byte array as ERAM byte.

Sometimes it works, sometimes it doesnt.

I am storing MD5 data into an array as a password thing on my device. I have a reset password button which writes the default passwords early in the boot, and then hangs until next reboot by pushing a button.

That works fine.

But if I programmatically send the password to write to EEPROM, it fails, and never writes. I am using the exact same code. And this code works on regular ATmegas. Just not the Xmega properly.

My subroutine terminates by doing a software reset on the processor. I even added a 1 second delay after the For loop for writing the bytes to eeprom.

I did the config eeprom thing.

Any ideas?

Edit: I did try adding this into my for loop:

enniom · Joined: 20 Oct 2009 Posts: 548

TechKnight,

when you post to ask for help, you should have the courtesy of posting some code we can compile in order to help you. What you have done here is meaningless.

DIM xxx as eram Byte? Word? Widget??

Config Eeprom = ???

Other???

techknight · Joined: 21 Apr 2008 Posts: 231

I did post the code! The whole subroutine block responsible for writing the information to EEPROM is in my first post!

What more do you need? Oh and the "Meaningless" comment was unnecessary, and rude, and automatically causes a raise in my defenses, depicting you as a troll.... Which you may or may not be.

Oh, and I have done alot of troubleshooting on my own, I only come for help online as a very last resort. I have figured out the problem is with ERAM arrays. single bytes have no trouble. But when declaring an ERAM array, thats when the trouble creeps up. As a last ditch effort I decided to use the NVM flag check to make sure I am giving enough time for the EEPROM to complete its write inside my FOR loop... That didnt solve it, as I mentioned in my first post.

Edit: Oops I forgot the important eeprom declarations.

Userbytes(16) as ERam byte
Adminbytes(16) as ERAM byte

And yes, EEPROM is mapped. I learned about that in the very beginning. inputbuffer is my I/O Buffer array that gets populated when I send datapackets to the XMega. There are header/length/addressing word checks which are excluded as they are not necessary, but should be aware of if your curious on the inputbuffer array offsets.

techknight · Joined: 21 Apr 2008 Posts: 231

I fixed it. Turns out I made a small mistake which for some strange reason works on all the ATmegas, but NOT the Xmega.

I was using this:

If Configversion <> 2 then
Configversion = 2

Well, my subroutine was running every time I rebooted the processor, reverting all the changes in EEPROM back to defaults. Whoops.

Configversion is an ERAM byte.

Changing it to this:

M = Configversion
If M <> 2 Then 'Check EEPROM for compatible Configuration, if not, Restore defaults

Fixed it. So I guess I cant use ERAM bytes directly in IF statements? Worked on the ATmega1284.

enniom · Joined: 20 Oct 2009 Posts: 548

You just proved my point.