- Thread starter mathieulh
- Start date
Reusing Sega's checkoff.exe doesn't exactly scream "open source implementation", it seems rather cumbersome to implement on Linux/Raspberry Pi as well.
In fact it wouldn't have worked with triforcetools.py (or subsequent implementations) at all even if you ran the sega executable separately because triforcetools.py sends
SECURITY_SetKeycode("\x00" * 8) everytime it loads a rom and the check gets reenabled everytime this command is sent to the netdimm, so you'd either need to disable the command (and use the checkoff.exe) as the command isn't needed for decrypted roms, or do it like we did and send the checkoff packet right after SECURITY_SetKeycode("\x00" * 8) is sent.
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Probably for the simple fact of the matter the team broke it down to a level where it’s easily implemented for a novice user.
Let’s at least give them the props for that.
Let’s at least give them the props for that.
definitely, that memory check have 2 purposes - detect game change and check game data integrity.
obviously people want to have ability to change games
this will require not some small patch, but more-less serious DIMM logic rework and rewrite.
Because: 1. I got my Naomi2 literally a week ago
2. I did not know checkoff was a thing or found by someone else since I don't literally go read every thread on AP and nobody seemed to talk openly about the stuff or document the DIMM firmware, (just like pretty much most stuff Arcade related it seems), so we literally had to discover this on our own after the fact.
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bobbydilley
Grand Master
Would be nice to see some support, rather than a "this is not new information" type message. As has been explained, a backhand comment on some random thread that will get no traction, and a fully usable and tested implementation that everyone can take advantage of are very different things.
This general tone of comments like this is making me understand more why folks like Finnisterre left...
support ? person asked how to disable DIMM RAM check, I've gave exact answer how to do this. not sure what else there should be.
he is not "left", and afaik constantly trying to get back, but can't because banned here
bobbydilley
Grand Master
I think there's a bit of a language barrier issue here, as that's not what I meant at all. Support in this sense means encouragement for our post, not technical support for your original post.
I'm sure we have cultural differences, in the way we talk / would expect to be spoken to, so this is possibly why your original message sounded demeaning to me - I'll pin this one down to that, and won't engage any further.
I'm sure we have cultural differences, in the way we talk / would expect to be spoken to, so this is possibly why your original message sounded demeaning to me - I'll pin this one down to that, and won't engage any further.
To be fair, and not to add to drama, there is a difference between:
- Finding some obscure sega tool forgotten in some game, seeing from the obvious filename that it disables the check, telling someone "use that stuff from chd watever" whenever someone asks about it, somewhere burried in the middle of some thread no one will pay attention to (and still not knowing how it actually works).
And
- Figuring out that there is indeed an app that disables the check, doing RE to figure out what it does, sniffing the packet/response from the tool to the dimm board and implementing it properly in an open source python script, testing said implementation to find out it doesn't work as-is with open source tools, finding the command that causes the "check off" packet not work in said open source tools, making a proper public post with your findinds and updated open source tools.
Thank you for this! What a huge difference in the time required to netboot games!
ok, I see the difference
as of real "support" from public - sadly, there is none, there is mostly bunch of people yelling "wow! cool! great!", but literally nobody even try to check/test this at real hardware, for practical use or if being asked to.
that's one of main reasons why I'm not much interested in making DIMM mods. for example, some time ago I've did patch where was implemented TOC read etc, so should be able to load games from regular burned CDs (not specially baked to LBA 45000), but there was no people willing to test this. so, why me investing my time on this if there is no single person in the world who really needs something for practical use ?
huh, we are both mature and skilled persons, and its pretty obvious we did it about the same way - grab that .exe-s from WCCF or Gundam, load in IDA and disassemble / decompile and check which data packet it sending
there was pretty few lines of code, it took minutes to analyze, so I can't even call it "RE work" and thought not even worth to be mentioned as some kind of achievement.
but yes, nice to have this properly explained and documented.
its like:
- we have a great idea! it will be nice if someone will do ....... !!! it would be so cool, we all want this!
- okay, I'll do that.
... some time ago
- done, is there anyone who will really use it at practice and may check if everything works as expected ?
- dead silence...
this happened quite many times...
I am not questioning your skills, I have seen some of your work and posts, you seem knowledgeable, I am not even saying this was hard work by any mean, it becomes quite easy once you have access to the leaked sega tools; What I am saying is, yes, I know you have the skills to do this, perhaps already did, but why make a fuss about how easy it is and so on after the fact? The point is we documented it (in a way) and made it easily accessible, before I made this release, I didn't even know checkoff was a thing, because it's seldom spoken of anywhere.
It doesn't matter if it took seconds, minutes or years to do, the point is, we did it, it wasn't (as far as I am aware of) publicly done before (and it wasn't privately shared to any of us either), and thus we shared it to the community.
Do I have any doubt that you could have pulled off the same thing? Not at all, that's not even the point I was arguing about, in fact you are most likely more knowledgeable than I am when it comes to anything Naomi (or Sega Arcade related), as I have mentioned, I only own a Naomi as of a week ago.
Raph_friend
Grand Master
I don't know what MetalliC is talking about, really. I'm one of who will test this method today and i think some others already did...
J
jassin000
Its ok man you can say it... We are all a bunch of pirates!
Well yea, I mean I am anyway.
Thing you need to understand is we (you and I) have radically difference views about life.
I for example don't honor or respect copy right laws, I don't personally believe a human man/woman can own an idea.
Sometimes I donate money to causes I believe in, sometimes I buy products I've already pirated to support the devs if I want.
But as a rule I could never do what you do for work (code) because I don't actually believe its work at all.
Thats not a personal attack, or an attempt to belittle you or how you make a living...
Its my own view point on just what constitutes work.
I'm in hardware, and yea I think that makes me hot shit... Because without me you've got nothing to run your precious code on.
Again, PoV is everything. I say if its not a physical object you can't own it, pure and simple.
