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griff3125

Atari Defender differences?

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So I've been loving Defender on the sio2sd and noticed that there are only 8 survivors that start in each wave.

I've tried six different versions, and they all have the 8 survivors.

I can't really see any difference between the versions, apart from v.5 being a trainer.

However, I threw in the official Atari cartridge, and it always starts with 10 survivors?

Anybody have any insights on this? I mean it's not a game breaker and hardly affects anything, but I'm curious as to why the differences?

Does anybody have a proper file that starts with 10 survivors?

Strange.....and thanks for any input.

 

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I think Griff means that in the Tosec dumps etc there's probably a V5 / alternate dump..Not official differences?

 

@griff, not played Defender in a while, is it possible that the versions you have may start on a harder level where there's less survivors to protect thus making the game harder..I know it does have difficulty levels...

 

Edit: Just looked, the manual says 10 lives but from the play screen its impossible to count ten survivors on the ground (well I could not, looked more like 6 every time), I suspect the squashing of the radar screen makes that hard.

Edited by Mclaneinc

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It's a bug caused by a badly done crack. There's a writeup and a

corrected .xex version by Fandal, on the atarimania forums somewhere

(I had a link to this, but it's no longer valid). There's supposed to be

10 humanoids, but whoever patched the ROM to defeat the copy protection

(stop it overwriting itself), patched a section of code that shouldn't

have been patched.

 

The really (to me) weird thing is, the patches are only needed for a

.xex version of the game. But later on, someone turned the patched .xex

code back into a raw ROM image and included it in the Holmes Archive,

and later it found its way into TOSEC, so this version was (still is)

found all over the 'net.

 

The 8-humanoids version isn't any kind of official alternate version, I

wish it could disappear forever, but that's not how the internet works...

 

The correctly dumped unpatched ROM (with 10 humanoids) lives here:

http://www.atarimania.com/game-atari-400-800-xl-xe-defender_1561.html

 

If it helps, the broken "8 humanoids" ROM image has md5sum:

e8d52b4aa33da38f99312f9aa8b48885

 

...and the proper one is:

8709351e76ec7c407e63c47ac53f8d19

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Thanks for the feedback everybody, it's easiest to tally the count at the end of the level, other then the "8", I've noticed no other differences but deep down it was driving me nuts, haha.

Urchlay, great post and thanks for the link!

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curt vendel released an alternate version (prototype)... but that's another story.....

technically there were 2 defenders for the ole 8 bit... and 1 for the 5200

 

the hacked/pirated 8 humanoid thing is just a massive bug resulting from a dirty hack..

Edited by _The Doctor__

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curt vendel released an alternate version (prototype)... but that's another story.....

technically there were 2 defenders for the ole 8 bit... and 1 for the 5200

 

the hacked/pirated 8 humanoid thing is just a massive bug resulting from a dirty hack..

 

What was different (if anything) with Curts proto?

 

Just keen to know..

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Here's a pretty good technical description of the 8-humanoids bug:

 

http://forum.atarimania.com/viewtopic.php?t=2356

 

I still haven't found the old forum post I referenced in my notes, looks

like I messed up the URL way back when I copied it. This was a few years

back when I was working on a commented dissassembly of the Defender ROM.

 

The only mystery remaining is... how did the person who cracked the game

and introduced the bug not *notice* the bug? It's pretty noticeable if

you finish level 1 without losing any humanoids: they get displayed in

a row which is obviously not centered and has room for 2 more. Maybe

that's just hindsight speaking?

 

I guess there's one more mystery: who the cracker was. Probably the

answer to that is lost to the ages...

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Did anyone go back and create a cheat version of the correct code or are all the cheat versions 8 humanoid only?

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Isn't the Wizard OSB only version 10 humanoids...I just tried to count them and sure it was 10...Basically its inv lives, inv smart bombs..

 

Won't post unless needed...

 

Checked via the details Urchlay posted and deffo 10 at the end level one..

 

 

Defender (1982)(Atari)(US)t Wizardreq OSb.atr

Edited by Mclaneinc
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Wow, after all these years I never noticed that the XEX version only had 8 humans. I tried the ROM version above and in deed it has all 10 humans. Is there a XEX version of Defender with 10 humans?

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Just tried 12 different xex's and they are all 8..Sorry..

 

 

Aha...One with 10 after a dupe check removal..

Defender.xex

Edited by Mclaneinc

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Isn't the Wizard OSB only version 10 humanoids...I just tried to count them and sure it was 10...Basically its inv lives, inv smart bombs..

 

Won't post unless needed...

 

Checked via the details Urchlay posted and deffo 10 at the end level one..

 

 

 

Thanks Paul... now... is there a XL/XE fix of that OSb cheat? :-)

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I'm just about sure my copy is a "locally cracked" one as we had access to the cartridge in the day and made a copy.

But I only seem to have it on floppy so will have to dig out the real hardware to check it out.

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I just edited this XEX using the forum post mentioned earlier. this now correctly has 10 lives. This is the first time I've ever done anything like that and it was only three bytes but please test!

 

Defender (1982)(Atari)(US) 10 Lives.xex

 

Oh this is XL/XE friendly too

Edited by Mr Robot
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Just tried 12 different xex's and they are all 8..Sorry..

Mclaneinc,

Thanks for checking them out. Defender is an iconic game that I'd imagine every Atari computer owner has spent some time playing. I guess back in the day I always used my cartridge. Would be nice to have a XEX version of the correct ROM. Besides playing it, Defender is my go to stress tester on new mods and checking out thermal stability of new purchased hardware. When I receive a new machine, first thing I do is run Defender in demo mode for an hour or so to see if anything overheats before I invest a lot of time on refurbishing and upgrading.

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Both myself amd Mr Robot have found you a proper 10 life xex...(reread my post now..)

 

Checked and working...Dunno if mine is edited or a real dump..Its works though :)

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Thanks Paul... now... is there a XL/XE fix of that OSb cheat? :-)

 

Sadly not in my collection, all OSB... Sorry :)

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Both myself amd Mr Robot have found you a proper 10 life xex...(reread my post now..)

 

Checked and working...Dunno if mine is edited or a real dump..Its works though :)

That was fast! Thank you and Mr Robot. I will have to wring it out later tonight when I can. This is why I love checking in at AA. The AA community has some very bright and talented members and I appreciate that we are all the beneficiary or this vast knowledge base.

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I appreciate that after the few days I've had......Wish I'd never seen that damn book now :)

 

But as with MrRobot, here to please, the more we share the more the enjoyment all around..

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