Protect Fuses to stop settings being wiped on firmware updat

Post by **Rob Thomson** » Tue Jan 10, 2012 9:56 pm

Why don't you protect your fuses? That way your settings are retained.

Sent from my iPhone using Tapatalk

Flaps 30 · Post by **Flaps 30** » Tue Jan 10, 2012 10:12 pm

Ahh! You mean that little menu that has the word WARNING at the top that tells you not to mess with it or your radio will require major work to bring it back to life. Not knowing which way or what that part of the software is doing and for why. I left it well alone.

Kayle · Post by **Kayle** » Tue Jan 10, 2012 10:25 pm

I think rob means, that you can protect you eeprom to overwrite during flashing your tx.

There is a fuse in your mega64, when it is set, the eeprom will not overite.

Kayle

Flaps 30 · Post by **Flaps 30** » Tue Jan 10, 2012 10:35 pm

I think I have got it Kayle. I take it what is being talked about is the 'Reset Fuses EEPROM - Protect' button. Does the delete button enable the writing of the EEPROM?

Kayle · Post by **Kayle** » Tue Jan 10, 2012 11:25 pm

i´m not sure. i don´t use eepe to write my fuses. perhaps Rob can answer your question ?

Kayle

Post by **Rob Thomson** » Wed Jan 11, 2012 6:46 am

I have only ever done this via eePe.

I am sure someone will give you the exact parameters before long.

In eePe you simply visit the 'fuses' menu and choose the bottom left option to protect them! 'Eprom Protect'

Despite the warning - I have never had an issue - across multiple radios!

Rob

RCPlaneHobby.com · Post by **RCPlaneHobby.com** » Wed Jan 11, 2012 3:59 pm

o.k. do I get this right?
"Fuse" means to "fuse" or permanently attach code so to speak to the tx. So that it is write protected when you flash your tx. I assume the reason for this is to keep all your settings and models while updating the firmware?
... or something?

Post by **Rob Thomson** » Wed Jan 11, 2012 4:26 pm

Correct. Not the most correct description... but the inherit meaning is correct

Post by **MikeB** » Wed Jan 11, 2012 4:37 pm

Atmel processors have a number of settings that control the basic operation of the processor. These settings include things like the type of oscillator to use. Atmel refer to these settings as FUSES. There are really just program bits like the flash program memory.
One of these settings is called EESAVE. If EESAVE is enabled, then when the chip is erased ready to reflash the program memory, the EEPROM is NOT erased. The default setting is to erase the EEPROM with the flash memory.
If you change any other of these settings (FUSES) it is possible to make it difficult, if not almost impossible, to program the chip the way we do. To program, the chip MUST have a clock running, if the fuses were changed to specify an external clock, and there isn't one. Then you cannot program the chip, or even change to fuses to specify an internal clock.
This is why there is a warning on eepe when you select to change the EESAVE fuse. I believe many have used this option in eepe to change their EESAVE fuse. I have changed my EESAVE fuse, but I have an Atmel STK500 development system and changed it using AVRStudio directly, I didnt need to use eepe. I regularly need to confugure fuse settings in Atmel processors for work.

Mike.

Spoogy · Post by **Spoogy** » Wed Jan 11, 2012 5:54 pm

Thanks Mike to clearing that out. I have been wondering what the f!"#k are those fuses, but I have been too lazy to find it out by myself.

Now, that's much much clearer - thanks.

Flaps 30 · Post by **Flaps 30** » Wed Jan 11, 2012 10:39 pm

Most of that makes sense Mike. It still does not remove that little nagging feeling, that I could easily end up with a situation, where I would have to get out an external clock generator to wake up the chip.

Does the reset fuses button put things back to normal?

Post by **Rob Thomson** » Wed Jan 11, 2012 10:59 pm

Yes. that is exactly what it does.

I have used the system on 4 different 9x's. Never had an issue.

Rob

G550Ted · Post by **G550Ted** » Thu Feb 09, 2012 10:57 pm

SHEESH!!!

I am neither an EE nor a Luddite, read every post in this forum as well as those on RCG and er9x, read the manual, whatever, but for the life of me cannot grasp what I should or should not do with the fuses option. The WARNING in eePe is ambiguous. The text in the box makes it sound like a good thing to do, but it is a WARNING! WTF? Why would I want to set the fuses? Why not? When? When not to? Are they not already set, and if they are a good thing then why are they not set by default already? Is it not a good thing to protect the EEPROM from being deleted when flashing? Why have the option to do this in eePe? Should this be a consideration for anyone having a SP board vice a hacked in programmer, or the other way around?

How about some more help on this issue for me and the other short bus riders.

Thanx,

Ted

Post by **cre8tiveleo** » Thu Feb 09, 2012 11:24 pm

Hands you a helmet, welcome aboard.

With companion 9x, you can set it to automagically backup your models for you. So you really don't need to set the protect fuse.

In eepe, if you don't protect the eprom, and flash your radio, it erases everything, the loads the new firmware. If you didn't set the protect, an didn't back up your model settings... You're sol.

If you set the protect, and write a new firmware, your model settings are golden and safe.

---
I am here: http://maps.google.com/maps?ll=44.003067,-79.457256

Post by **erazz** » Thu Feb 09, 2012 11:26 pm

I tried to make it as clear as I could. You CAN and perhaps SHOULD set your fuses to protect. I have tried to make it as foolproof as possible.

It's a warning so you know it's a non-trivial operation. You really should make sure your programmer works reliably. Stopping in mid-write may brick your radio.

That being said, it is a very automated processs. You plug in your radio - press the button and wait.

Post by **erazz** » Thu Feb 09, 2012 11:29 pm

Regarding automatic backup and rewrite.
I don't have a problem reading the EEPROM but writing it back when you could just prevent it from being erased..... Why?

Guys, if the reading and writing of EEPROM goes well than seting the fuses should not be a problem.

Post by **cre8tiveleo** » Thu Feb 09, 2012 11:31 pm

Just do it!

---
I am here: http://maps.google.com/maps?ll=44.003067,-79.457256

Post by **erazz** » Thu Feb 09, 2012 11:33 pm

I'll take another crack at making this more user friendly.

Back in the earlier days we had a rash of "bricks" meaning people had somehow messed up their fuses and "bricked" their radio requiring an external oscilator to get it back up. I guess we're carrying around the scars from that. Truth be told I have not heard a single mention of a brick since we started using eePe.

G550Ted · Post by **G550Ted** » Thu Feb 09, 2012 11:38 pm

OK guys, now that's clear and simple like I need. Inasmuch as both of my radios with SP boards are working fine I will "set" the fuses on both. Something clear like this needs to go in the wiki.

Thanx,

Ted

I have learned to brush my teeth but still require assistance tying my shoelaces.

Post by **erazz** » Fri Feb 10, 2012 12:00 am

As we speak I'm writing something clearer and more user friendly.
I'm also restoring ther ability to reset the fuses to factory default.

This is all purely cosmetic. Feel free to set the fuses with your current version of eepe.

G550Ted · Post by **G550Ted** » Fri Feb 10, 2012 12:18 am

Much appreciated! Thanx again.

Ted

Post by **erazz** » Fri Feb 10, 2012 1:56 am

We try to please

Post by **cre8tiveleo** » Fri Feb 10, 2012 3:37 am

much friendlier warnings... Cr8tive_leo approves.

Westy · Post by **Westy** » Fri Feb 10, 2012 9:37 am

Westy Approves Also

Keep up the great work chaps!

Post by **jhsa** » Fri Feb 10, 2012 9:56 am

JHSA approves cre8tiveleo's and KiwiHeliguy's approval

Post by **erazz** » Fri Feb 10, 2012 12:31 pm

Do you guys approve each other as well?

G550Ted · Post by **G550Ted** » Sat Feb 11, 2012 12:49 am

My fuses are set, and I approve of another glass of wine.

A toast to you erazz!

Ted

openrcforums