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Soo i was going to region mod my genesis 2 when i realized that there isnt any guides anywhere for this particuar board. It's a "PC BD MD2 VA2 USA"
I recently modded a european mega drive 2 without any problems, but they do not look the same. So i wonder, Where am i supposed to solder?
Here is a pic of the board:
https://www.dropbox.com/s/2htd4pslb3..._0608.JPG?dl=0
Hope anyone can help :P
As I understand it, any PAL machine is the same only with the traces to cut and the points to solder in different locations. The same principles apply across all board types regardless of locations. I have modded 2 MD model ones (PAL) and one NTSC Nomad. The principles were the same, though the points to cut for an NTSC model differed slightly (not sure off the top of my head exactly).
If you look for the correct jumper pairs and proceed as if it were a model one you should be OK. There are far more expert members in this area than me I must say though.
Check out this thread I started based on my Nomad butchery...
http://www.sega-16.com/forum/showthr...thread-(sorry)
You should get all you need from here.
Ok, so lets see if understand this correctly. Is the jp the same regardless of the circuitboard?
Skoldis take a look at this thread. http://www.sega-16.com/forum/showthr...egion-mod-help
Cleeg is 100% correct. An oddity that was found out was model 1 VA7s (with a particular "main"ic) don't like to be switched to 50hz, doesn't bother you, just a bit of jolly interesting.
I have modded a few va2.3 Genesis'ssss (similar to a va2) to suit my Aussie pal games and they are fine.
I should have made it clearer in my earlier post, all the wisdom I espoused came from OMP. I only know it after a massive PM mithering campaign directed at him.
Thanks for the help! I successfully made the mod with 2 switches.
Now theres another problem though. when playing palgames it's in black & white.
I am using it on a paltv, i'm from sweden so all my games are in pal. I am not using
the regular antenna cable but an rgb cable that goes in the same slot.
edit: what i mean is that when i set it to 50hz the games is in black & white
You're getting a grayscale picture because the console is generating an invalid color subcarrier frequency. You would need to add a separate circuit for the PAL color subcarrier frequency (4.43361875MHz) to get around this.
If you browse through this thread, it may help you along.
http://www.sega-16.com/forum/showthr...t=region+model
In there are links to videos that show colour correction and if you are still able to (or would like to) convert it to a single switch mod.
Oh, all good Cleeg! How are those consoles going for you matey?
ok so if i understand this correctly i need a 4.43361875MHz oscillator? Where do i get one?
Can anyone explain to me why the pal mdII i regionmodded works perfectly with color regardless of
the hz, and the G2 isn't?
Hey hey, butchered up my Mega CD a bit, got the mod working very briefly but had to remove all I'd put in and thank God it still works! I'm waiting on some new chips with the Olivera Japanese region free BIOS. Luckily my unit has a DIP socket already in situ.Quote:
Originally Posted by omp
The Nomad's working great and I was able to fix an incomplete mod on another afterwards, cheers!
@ Skoldis, are you using a true RGB SCART cable? If I remember rightly you need one to make 50hz stuff look right. The reason I think this is is because my Nomad has a new screen routed from the AV out using a composite video signal that gives a monochrome picture in PAL mode. When I plug the Nomad into my telly with an RGB SCART cable I get a colour picture at 50hz.
Yes, i'm pretty sure it is. It's the same i used on the pal, and that one shows both 50hz and 60 hz in color. I think i have another one though, i'll see if i can find it and try it.
ok, so i tried with a rca port for video output, but its still b & w.
Please correct me if I'm wrong. I thought if you were using RGB the subcarrier frequency didn't matter; it only matters if you want to keep Composite or RF video?
There is a fellow in Assembler's Forum who made a nice through hole board with the Oscillator on board for the different subcarrier frequency but he did use a PIC since it's the Switchless Mod. Might be worth asking for one from him:
http://www.assemblergames.com/forums...l=1#post777792
This is the cable i am using:
Attachment 9574
Thanks for the tip Helder!
i talked to my friend who own the pal mdII i regionmodded, apparently his also displays 50 hz in b&w.
This was a pal mdII from the beginning so i really don't understand this. I can admit that i actually don't know much about the
electronics, i always just follow guides i find online, i am however good at soldering when i know what i'm supposed to do :P
If you don't want to buy a board from the guy I linked to he seems like a nice guy and will probably tell you how to wire up the 2 oscillators on some perf board and you can add it to the switches you have now.
If you are using scart rgb cable it should be ok. Maybe your tv has an scart connection but is composite only?
^ Could be right, SCART sockets are non standard animals, rather annonyingly. Try a different socket or TV. Some are labelled RBG even.
i did try with different tvs and sockets. i tried to connected it directly to the rgb slot, through a scartconverter & i even tried soldering a separate rca port, but it is still always b&w. I made the mod by soldering the cables at the jp points.
@Helder I tried to register at assemblergames but whatever username i choose it says its already taken :P (i even tried with gibberish)
I can ask him for a schematic and see if he will provide one and you can adopt the design with the switches.
that would be really nice! thanks!
He joined the forums and is awaiting admin approval of his account and he will post schematics of his work.
That's awesome! thanks!
Hi there! So Helder told me to come check-up this thread.
First of all, I'm not a natural English speaker, so I excuse me for all the mistakes I'll wrote.
Also, my board is kinda in work in progress.
So I made a board for the Genesis 2 which auto switch to PAL or NTSC Color Crystal subcarrier. It's an adaptation of a similar board I designed for the Genesis 1, but with automatic function (the other use a switch to allow forcing signals)
Here's the scematic:
http://uppix.com/f-Genesis2_VideoBo54373a9c0017d073.jpg
Here's a exemple of a board. I'm not happy of the current design, but at least it corrects the flaws of my earlier prototype
http://uppix.com/f-Genesis2_VideoBo54373b560017d074.jpg
- You need: Ground, +5v, Video signal (named as MB7), Original Crystal signal (named as MB6) , feed to the video chip (named as PIN6). I found a great place at R61 and removing it (my board includes the R61 as the 10k resistor)
- It analyses the signal incoming to pin 7 of the video chip (or from the JP3/4, it's the same signal), compare to another logic (Low or High) and a 74HC052 will "open" one or another circuit with the proper Crystal:
- if identical, uses original crystal signal
- if not, then if ground uses PAL
- if not, then uses NTSC
- Since the Genesis 2 doesn't have a Crystal Driver, and 2 pins Crystal are more easy to find than 4 pins (especially 4.43Mhz ones) I had to use a 74HC04 as a driver.
- It works fine with my switchless board, but since it's based on the NTSC/PAL logic on pin 7 it could easily fit with your switch mod.
Tested with two Genesis 2 VA1.8, one with a Fujitsu MB3514 and the other with a Samsung KA2195D. I've order two Sony CXA1145m to have a decent output and made some Svideo mode :D.
Here's some pics of the installation:
http://uppix.com/f-IMG_13785428b8d70017b228.jpg
http://uppix.com/f-IMG_13795428b90c0017b229.jpg
Note that it works perfectly with the KA2195D, but the MB3514 doesn't like "on-the-fly" change, but works fine on cool boot.
Hi, I'm the dude that Helder is talking about. I made a long post 3 days ago, but it seems the moderator didn't approve it (yet?).
I'll wait a bit longer but I'll eventually re-post the whole thing.
Thanks for that! i don't know how this forum works with that :o
Post is up. Thanks admin/moderator. ;)
Once you have a solid design you should sell these as I'm sure they will sell well.
Just wondering if you really need that variable capacitor at the bottom or can 30pf be used in it's place?
Not sure if people will be interested in this board.
For PAL Megadrive you can just use only a single crystal (4.43mhz crystal with NTSC refresh rate, a.k.a. the famous PAL 60Hz) and have way simpler board. For NTSC Genesis , since NTSC 50Hz (PAL refresh rate but with a 3.57Mhz color subcarrier) is freaking the sh*t out of most US TV, at the end you still need a TV accepting PAL signal... My TV (BRAVIA KDL-40EX500) accept NTSC-3.57, PAL-4.43 and even NTSC-4.43. PAL-3.57 is a no-go. So I'm always questioning about having the 3.57mhz crystal is relevant.
The 2 only good things about my board are:
- True signal for color subcarrier frenquencies and no aproximated derivated value from the main clock (increase quality from what I saw on NTSC system)
- Can do both system and switch NTSC/PAL
But it's not the magic solution for having color on "PAL" system with a NTSC only TV that I hoped for when I designed it at the beginning.
I still be easier and better to plug the system in RGB anyway.
For the capacitor, I saw some other crystal circuit with 30uF indeed, but from my tests the trimmer is helping to some "waving" issues and stablizing some "vibrations" of the color on screen.
Is it possible to take the R, G, B, C-Sync, Ground, and +5v from the A/V port on the Genesis and encode it to whichever standard you like in an external box? This is what the 32x sort of does I think.
No the 32x is using a crystal subcarrier and a similar circuit. I'm already working on a similar board for it.
http://uppix.com/f-Sega_32X_CSC53d55dad00171aef.png
This 32x is just rendering stuff on top of the genesis RGB render (like a layer). The fact that the 32x displays a better image on S-video is, I think, due to the fact that it is using a true crystal subcarrier an not a derivated signal.