Build Your Own Arcade Controls Forum

Arcade Collecting => Merit/JVL Touchscreen => Topic started by: tandrews on January 14, 2017, 05:15:52 pm

Title: Megatouch XL Reverse Engineering Discussion
Post by: tandrews on January 14, 2017, 05:15:52 pm
After speaking with some people. I am pulling as discussion of my work. Things are pretty hairy legally and I can't afford any trouble. Until I hear further, no more information will be published or discussed on my part.
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: obcd on January 14, 2017, 05:38:39 pm
I used dosbox to reverse as it has a rather good buildin debugger.
It was an older version without the cd check and with the square protection dongle.

Had to alter the dosbox sources a bit as the memory window used to access the nvram was hardcoded for the emm driver.

I basically logged the password that was sent to unlock the dongle and wrote a small program that used it to unlock the real hardware dongle so that I could read it's protected contents.

Next step was adding some routines to dosbox to emulate the dongle behavour.

And I had to choose a different sound driver. It was in the dig.ini file if I remember well. Believe they used something like "Miles sound system" which now became freely available.

It works for 95%. some transitions in the games are not correct, probably due to the video hardware not being correct emulated.
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: tandrews on January 14, 2017, 05:44:36 pm
[Removed for legal concerns]
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: obcd on January 14, 2017, 05:59:29 pm
Once you got things worked out, you can use it on real hardware as well.
It's for instance possible to jump to a TSR interrupt routine when an io is read or written.
It might in theory be possible to emulate the security dongle like that, but it's difficult stuff.

I assume your key is the dallas button style which uses the one wire protocol.

I might still have the IO ports I figured out for the io card. Just let me know if you have any use for them.
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: tandrews on January 14, 2017, 06:06:37 pm
I was attempting to do something with a TSR but yeah, its more difficult for sure.

I've invested too much time into fixing the fixup records to stop now. I have written code that can search for a given record and i can then patch the record. This will allow for easy loading from file.

I am generally pretty good at reversing stuff, but hardware based things I can be a bit weak with. Your kung-fu is definitely sharper than mine:P
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: obcd on January 15, 2017, 05:30:47 pm
There are many roads to the same destination.

If you could spare your image and your dongle contents, I could try to get it going in dosbox emulation.
I would benefit as it might be an option to update my system and you could benefit as you could use the emulation environment to test your modified code. It would be a win win for both.
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: tandrews on January 15, 2017, 06:37:30 pm
That'd be ... very nice. I will happily share my files. just send a PM
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: ice2921 on January 15, 2017, 07:02:18 pm
So in layman's terms what exactly will this allow you to do?
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: tandrews on January 15, 2017, 07:05:13 pm
[Removed for legal reasons]
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: lilshawn on January 25, 2017, 03:00:48 pm
I'm going to go ahead and allow posting reverse engineering information and files for the older XL era machines. (please nothing for the force/ion machines for the time being) I will also create a sticky post too as well.

(http://forum.arcadecontrols.com/index.php/topic,153088.0.html (http://forum.arcadecontrols.com/index.php/topic,153088.0.html))
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: mahkeymike on January 26, 2017, 02:10:35 pm
You should probably ask that guy over at KLOV to take down that 2010 patcher if you have legal concerns?
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: ed12 on January 26, 2017, 02:17:04 pm
truly
i think ppl are looking to deep into this
a=merit as we know it is gone
b=new merit is server bound
so truly we can not buy there hardware
and or repair stuff
to me that means wild west time if u catch the meaning ?

ed
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: mahkeymike on January 26, 2017, 02:29:37 pm
what do you mean by new merit is server bound?
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: ed12 on January 26, 2017, 03:50:57 pm
2015

ed
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: mahkeymike on January 26, 2017, 04:15:34 pm
2015 wut?
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: lilshawn on January 26, 2017, 07:08:40 pm
the ML-1 is tied to a megatouch server for authentication. if you didn't get the patch to make the system offline, you are SOL and the unit is a brick now.
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: mahkeymike on January 26, 2017, 07:30:35 pm
the ML-1 is tied to a megatouch server for authentication. if you didn't get the patch to make the system offline, you are SOL and the unit is a brick now.

There are still a few Vendors that sell the Offline Hard drives. They cost $300
Title: Re: Megatouch XL Reverse Engineering Discussion
Post by: tandrews on January 27, 2017, 05:38:20 pm
You should probably ask that guy over at KLOV to take down that 2010 patcher if you have legal concerns?

Not sure what you could be referring to? Last I checked my name isn't on it. I never released mine.