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Ohh Yea does this look familier (Caution Message)


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First off Here...

 

item3="This Navi product is intended solely as a driving aid. Review instruction manual and select route before driving. Navi is not a substitute for your attentiveness, judgment, and care while driving or moving your vehicle. Always observe safe driving rules and driving laws, and follow road signs even if they contradict Navi's instructions. By pressing OK key, you accept the license agreement in the instruction manual."

 

Second now that this had been found we can find a work around for it!!! yay...

 

Anyway its located in the MainRes.Res file (use whatever zip u got) and its in the main.cfm file...

 

now to find out a way around it.

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Well I went into the MainRes.Res file and edited the message. All I did was change the text. My plan was to see if the text did indeed change on the nav unit, then we'd know for certain we were on the right track. (We've had a few red herrings within the navi software after all.)

 

So I made my new MainRes.Res file, copied it to the F700 after moving the original to MainRes.bak. Then I rebooted and waited for my new message.

 

And waited, and waited. The 'starting...' screen was there for ever. Well, big sigh, didn't work, but I figured no worries, it just wasn't reading the new MainRes.Res file. Turn it off, put the testmode card in, turn it on.

 

And wait. And wait. And wait.

 

Oh crap it's not going into test mode....

 

I start thinking, what do I do? Kill power totally? Cut the yellow line? Hit the reset button? I can't believe I've bricked it. Shit.

 

Well, I kill power then with crossed fingers, turn it on again. Huge sigh of relief, it goes into test mode. I delete my modified MainRes.Res and restore the backup. Toggle power and it boots up ok. Well mostly ok. It has definately done a master reset on itself, erased some settings etc. But it isn't bricked!

 

Yay!

 

I don't know what I did wrong. Maybe it does a CRC check on the MainRes.Res file. Whatever happened, it gave me a good fright this morning.

 

Think I'll sit back now and let someone else work on the safety message for a while. :wink:

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It's possible I messed something up, I've got a cold or flu or something and I'm kind of dizzy and befuddled. But I thought I had done everything ok, all i had changed was the strings table to edit the warning text.

 

Whatever I did though, it prevented the thing from booting, and made me think it was bricked when testmode failed the first time around.

 

If they did want to ensure people didn't tamper with the main software though, doing a crc or some other kind of check against the mainres.res file would certainly make that a lot tougher.

 

As an aside, I wonder if this is part of the reason the thing boots so slowly - it has a lot of compressed files to uncompress before it can actually do anything. That doesn't seem like a good design, IMHO.

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Before reading my post, check here first and look at his caution screenshot:

http://www.avic411.com/forum/viewtopic.php?t=17590

 

if a CRC check goes by a certain exact number created by the caution file, then wouldn't changing the background of it too change that number??

 

no the background is in the image.res they might not of put a security on that... mainres.res could be different i was looking in that file but didnt try any changes so :/

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Well how exactly does a CRC make sure everything is in check? does each character have a certain value? does it count how many characters are in the actual text? It has to follow a certain guideline to know that the file is not the original, even when the new one has been renamed, or it could maybe be as simple as a hidden file within the original that hasn't eben included in the new one...

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"Cyclic Redundancy Check

 

 

Definition: (1) A method to detect and correct errors by adding bits derived from a block or string of bits to the block. (2) An algorithm to compute bits characteristic of a block based on the algebra of polynomials over the integers, modulo 2. (3) The characteristic bits of a block.

 

Also known as CRC.

 

Note: Large blocks may be probabilistically compared by precalculating the CRC for each block, then comparing their CRCs. If the CRCs are different, the blocks are different. If the CRCs match, there is a small chance that the blocks are actually different. This probability may be made arbitrarily smaller with more CRC bits. "

 

 

From what I've read, crc mainlly concerns data transmission, and reception??????????????????????????????????????????

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CRC was used in the past for data transmission (Usually the methods used in communications are much more complex than CRC and sometimes will involve a combo of horizontal and vertical redundancy checks along with CRC), but it is also used a lot to check the integrity of a file.

 

Example: Automatic error recovery.

 

Your computers operating system tries to start up and fails. Next startup it runs a CRC check on all important files and finds one that does not match the correct CRC. Next, the operating system replaces the bad file with a known good copy. Voila the system will now start up.

 

CRC is basically a universal "make sure the file is good" checker.

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