Forum - MCS Electronics

 

FAQFAQ SearchSearch RegisterRegister Log inLog in

When to Set the Lockbits using Atmel Studio

 
Post new topic   Reply to topic    www.mcselec.com Forum Index -> Various
View previous topic :: View next topic  
Author Message
Thehon1985

Bascom Member



Joined: 20 Feb 2007
Posts: 8

blank.gif
PostPosted: Thu Dec 03, 2009 8:24 pm    Post subject: When to Set the Lockbits using Atmel Studio Reply with quote

I use Atmel Studio to burn my programs to my chips. I want to have it so no one can program or verify the chips after I burn them. Do I burn the program and then set the lockbits?

Also, if I make a mistake and want to re-use the chip after setting the lockbit to not allow further programming, what can I do?

Matt
Back to top
View user's profile
AdrianJ

Bascom Expert



Joined: 16 Jan 2006
Posts: 2470
Location: Queensland

australia.gif
PostPosted: Mon Dec 07, 2009 11:19 pm    Post subject: Reply with quote

Burn the program first, then the fuse bits, then the lock bits last, maybe even after you have tested to make sure the device is functional.

The lock bits only disable reading and writing the program, depending which bits are set. They do not prevent you from doing a chip erase.
That will clear both the lock bits and the program, so you get back to a blank chip.

Be aware that it is possible to disable both the JTAG and the ISP programming interfaces by setting the relevant fuse bits. Once you do this, you can only recover with a parallel connection and high voltage programmer.

_________________
Adrian Jansen
Computer language is a framework for creativity
Back to top
View user's profile Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    www.mcselec.com Forum Index -> Various All times are GMT + 1 Hour
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum