GGTV (Game Gear TV-out) wrong colors?

[cr4zymanz0r]

I received a viletim GGTV board the other day and did a preliminary install far enough to test composite video. It works, but my colors are wrong. At first observation it looked like maybe the colors were wrong as it appeared that red, green, and blue colors were instead showing blue, red, green. So next I connected RGB thinking maybe I could just swap the signals as a quick test, but that still gave me (different) incorrect colors.

Here's what colors look like when wired up "correctly": http://i.imgur.com/ArXaDXB.jpg

My initial guess was on viletim's instructions (http://etim.net.au/ggtv/ggtv.htm) he has images for where to solder on 1 ASIC and 2 ASIC style Game Gears. However, my Game Gear is a slightly different model than the one he shows. His is an 837-7398-02, while mine is an 837-7719-01. Mine looks very similar in component layout so I went with his intructions.

I found different instructions posted specifically for my model that I found here http://sonichacking.com/hardware/gg_2_asic_tras_hd.jpg that is basically the same directions but soldering to the other side of the same resistors. I tried this and everything looked the same on the output as the original instructions.

Has anyone else encountered an issue like this?

2 things to note:
1.) I've already emailed viletim, but I don't know how long it'll take him to respond and I'm anxious to continue my project
2.) This appears to be a newer revision than any documented on his store or installation instructions. It looks very similar, but while the shown 2.1 revision has D0, D1, D2, and D3. This also has pads for D4 and D5 above them (but I haven't seen any instructions for them. I assumed they might be for programming/firmware updates).

[CkRtech]

Hey cr4zymanz0r,

The side of the components you solder to is tied to the revision of the Game Gear you own. Since you just ordered yours, you should have the 2.1 revision and follow those instructions. I doubt there is a special version of the 2 ASIC style boards that would force you to use a different soldering configuration. The 2.1 guide (technically the 2.0 since 2.1 is just minor changes) should be what you follow.

Can you double check to make sure that you connected the correct wires for D0 through D4?

Notice that with your GG board oriented so that the solder points are in the bottom right corner and contrast wheel in the top left corner (like in your photo from the sonichacking website), the D solder points in order from left to right are 1, 3, 0, 2.

I am guessing that perhaps you wired something like D3 on the GG to D2 on the GGTV, etc., etc.

Funny you wrote this. I was actually doing case work on my Game Gear tonight so I can mount the controller port and video out port for my GGTV. It is a great board!

[cr4zymanz0r]

I've tripled checked that all the connections are going to the appropriate solder points labelled in the instructions. Also, my board shows that it is revision 2.3.

[CkRtech]

Ahh interesting. Mine is actually 2.2. Made note of that today as I was working on it.

Are any of your D lines grounding out by chance? Any bridged connections?

...any luck?

[cr4zymanz0r]

Yes, I've checked all the connections from the GGTV to the Game Gear with a multimeter. I'm not finding any issues as far as following the instructions go. Only other thing I know to possibly do is start swapping randomly swapping the D0, D1, D2, D3 inputs to see if that changes colors on things, but I'm weary of that potentially damaging something since I don't know what the signals are and what the GGTV is specifically doing with them.

[viletim]

The GGTV is up to version 2.3 at the moment. This one has some extra pads D4 and D5. This is for the later version Game Gear units which were released in the US. It has a different, incompatible display interface to the more common 1 and 2 ASIC models. I haven't implement this yet so the extra pads currently do nothing.

I also made a change to the logic. It synchronises the colours from the C.Sync signal instead of the H.Sync. I did this so the H.Sync wire wouldn't be necessary. This point is quite hard to solder on the 1 ASIC board (solder to a via) and is not available at all on the later model with the different interface. So it seems the new method of synchronising the colours doesn't work consistently between the 1 and 2 ASIC models. I didn't test it on the 2 ASIC boards because mine's broken.

Cr4zymanz0r, do the colours remain consistent with each power cycle? If so, you should be able to swap the r/g/b wires around to get a correctly coloured picture. Only for RGB of course.

[cr4zymanz0r]

The colors do stay consistent between power cycles. However, I did try swapping RGB wires around and that only gave me different wrong colors.

If Hsync is no longer necessary, could that be interfering with the colors since I have it connected? I could try disconnecting it when I get home.

EDIT: Disconnected hsync, but colors were still the same level of incorrectness. Stumped at the moment until further suggestions.

[yxkalle]

The colors do stay consistent between power cycles. However, I did try swapping RGB wires around and that only gave me different wrong colors.

If Hsync is no longer necessary, could that be interfering with the colors since I have it connected? I could try disconnecting it when I get home.

EDIT: Disconnected hsync, but colors were still the same level of incorrectness. Stumped at the moment until further suggestions.

Maybe you didn't try hard enough?
http://imgur.com/i0rOztX

Code: Select all

Input:   Output:
Red   <- Green
Green <- Blue
Blue  <- Red

[cr4zymanz0r]

The colors do stay consistent between power cycles. However, I did try swapping RGB wires around and that only gave me different wrong colors.

If Hsync is no longer necessary, could that be interfering with the colors since I have it connected? I could try disconnecting it when I get home.

EDIT: Disconnected hsync, but colors were still the same level of incorrectness. Stumped at the moment until further suggestions.

Maybe you didn't try hard enough?
http://imgur.com/i0rOztX

Code: Select all

Input:   Output:
Red   <- Green
Green <- Blue
Blue  <- Red

I can double check to make super sure sometime today. But why are you posting a screenshot of the correct colors? Did you also get a 2.3 revision GGTV that you were using on a 2 ASIC Game Gear and had to do this?

EDIT: derp, looked again and realized this does appear to be my screenshot cropped but with colors corrected. I'll test again before the day is over.

[Fudoh]

wild guess: that's your snapshot with the color channels exchanged in software. This means you should be able to achieve the same in hardware by switching the pins as described.

[cr4zymanz0r]

Swapping RGB in the order mentioned above did indeed give me the correct colors. I guess I accidentally skipped over that combination in previous testing. While this will fix RGB for me, I'd like composite and s-video to be correct as well.

What are my options for this? The only thing I can think of (though it'd be kinda a pain) is to lift the RGB input pins of the GGTV video encoder chip and reroute RGB to it appropriately.

[RGB32E]

Removing the SMD caps might be easier and safer than lifting the encoders legs! Or, program the GGTV with an updated FW?

[viletim]

Swapping RGB in the order mentioned above did indeed give me the correct colors. I guess I accidentally skipped over that combination in previous testing. While this will fix RGB for me, I'd like composite and s-video to be correct as well.

What are my options for this? The only thing I can think of (though it'd be kinda a pain) is to lift the RGB input pins of the GGTV video encoder chip and reroute RGB to it appropriately.

In the unlikely event you have an Altera USB Blaster programmer lying around, I could send you the software to reprogram it. Otherwise, I'll sent you a replacement GGTV board.

Does anybody have a 2 ASIC Game Gear for sale?

[cr4zymanz0r]

In the unlikely event you have an Altera USB Blaster programmer lying around, I could send you the software to reprogram it. Otherwise, I'll sent you a replacement GGTV board.
Does anybody have a 2 ASIC Game Gear for sale?

Altera USB Blaster programmer, is this the same one that's used to reprogram the NESRGB? If so I have one.