Feedback MARIAdigitizer (for Atari 7800)

[c0pperdragon]

Please share you experience and suggestions with this modification board. Pictures are always appreciated.

[CrossBow777]

Still waiting on my order to arrive. But is there any specifics folks need to be aware of regarding the Mariadigitizer? I know you have emailed me directly with some information.

Where are the profiles needed for using the Mariadigitizer? Is there a newer beta release for the RGB2HDMI that includes them or?

[c0pperdragon]

I hope that everything you need is on the project page (which is also linked from my product page in my store): https://github.com/c0pperdragon/LumaCode/wiki/MARIAdigitizer-(for-Atari-7800) I also hope that your shipment eventually gets through US customs. best regards Reinhard

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[CrossBow777]

According to the tracking, My last order placed just a week ago, is already on the truck out for delivery to my house later today. So, yes it seems it cleared through customers quickly this time around.

Thank you for the information I will look it over and report back as needed.

[CrossBow777]

Okay, initial findings on NTSC are really good!!! Most games work just fine but any games that I guess are using some strange video modes / resolutions that change between game screens do cause some issues. Also, there are issues with the vertical positioning with games being too high and then when the V offset is adjuste in the RGB2HDMI to bring them down, then another game ends up with some of the lower graphics being cut off and causing me to have to raise the V offset to bring the image back up. I was able to finally get around this by increasing the Max V height setting to about 250 and my V offset to about 28 seems to be good for nearly all games.

Initially I couldn't find any phase sample settings to bring in a good noise free picture. And I still haven't but I've nearly got it there by using phase sample 7 (315 Degrees), and changing the DAC-E: Sync to about 015 (.019v). But even some horizontal noise lines will show across the screen for a frame randomly or some on some games there will be a small white flickering pixel dots in a column somewhere on the screen.

So perhaps just more tweaks with the various Dac settings might dial this in fully but so far where I have my settings seem to be about the best overall I can get. I've attached some screen shots to show the results.

Here is the remake of 7800 Donkey Kong known as Donkey Kong PK direct HDMI capture from Maria digitizer:

However between levels on the How High can you Go? screens, Kong looks messed up but then it is correct once the game level starts: Here is a sample of what that looks like:

Here is BallBlazer showing some of the random noise that still occurs on the screen occasionally. I've found that BallBlazer is the worst offender at causing these to happen. I've also had the 7800 just flat out lock up while playing this game and it didn't used to do that before.

Here is a screen capture from the new Tiger Heli that was released. This game looks pretty good overall but does have a few noise pixels that still appears as can be seen in below:

And finally, here is the color palette screen from Mike Sarrna's 7800 Utility Cart ROM that I use for consoles testing and services.

[CrossBow777]

In doing more testing, the 7800GD menu is completely non readable. It isn't being rendered coorectly at all from the digitizer it seems. Also, any game using the 320 graphics modes or really seem to stress the Maria with lots of DLIs will cause nasty vertical streaks and graphics corruption on the output that isn't present when I'm viewing via s-video output on the same console. I've attached some more screen captures.

This is the menu screen from the7800GD.

Title screen for 1942

Game play screen capture of 1942 game play. Lots of pixel noise that isn't able to be adjusted out that I've found.

This is game play capture from Lewis Hills Keystone Koppers for the 7800. All of the games made by Mr. Hill (Muddyvision), will do this across he screen.

[c0pperdragon]

Thank you very much for the tests. So, the MARIAdigitizer seems to be far from finished.

The issue with the random pixel noise can not be solved by the digitizer but it must be a problem at decoding the lumacode on the side of the RGBtoHDMI. It seems that specific colors are especially hard to receive. Mainly the blue in Ballblazer and 1942. It is no wonder that this now happens with the MARIAdigitizer, as it pushes the data transfer rate to the maximum used in all machines (equal only to the Atari 8-bit). Similar things happend at my tests when I have a non-optimal ground connection between the console/computer and the RGBtoHDMI. I really do suspect your cables.

A true error of the MARAIdigitizer is the messed-up 320pixel mode. It seems to switch to the high-res mode, but
the colors are generated all wrong (Donkey Kong intermission scene, 7800GD menu, 1942 title).

I have no idea yet, what is going on with Keystone Coppers. It seems to use 160 pixel mode throughout, so something else must cause this complete screen corruption.

[CrossBow777]

You continue to mention my ground connections but here in the case of my lab 7800. I'm not using the 3.5mm combined jack. This 7800 has a UAV installed and has for years. So I have dedicated RCAs and S-video that I can use at the same time to compare. But with these maria digitizer tests. I'm using the RCA jack you provided directly cabled off the maria digitizer. So I'm using one of the short rca break out cables that come with the RGB2HDMI + audio for lumacode cables that you provide. So I'm really not sure how much more I can do to change that around? I'm also using the USB on the monitors to power the RGB2HDMI because of the 4 different spare phone charges I've got laying around. Only 2 seemed to NOT cause pixel noise. I'm thinking of trying to power the RGB2HDMI using one of the actual power supplies from Ada Fruit to see if that is the best all around solution. How are your powering your RGB2HDMI that you have found works the best? Because aside from that, everything else I'm using here is provided by you in my Maria testing from the console side to the RGB2HDMI.

With the exception of Ball Blazer and a few little horizontal lines that crop up here and there, most of the original released title games seem to be working fine and look good with the adjustments I've made on the RGB2HDMI side. It is really just the newer games and homebrews that are causing the most issues. Likely these games are using some video tricks to pull off what they are doing.

Another game I tested although I didn't take any captures since the game is hard to get these days is Rikki and Vikki. It is an unplayable mess and I believe it too is using one of the 320 modes. But it has severe sprite corruption throughout from title screen to opening intro cinematics to game play.

[c0pperdragon]

About the pixel noise: Sometimes it helps when you turn off the 75ohm termination in the Sample Menu. If you do this, you also need to double all sample voltage threasholds.
For my own setup, I power the RGBtoHDMI with a 2000mA 5V power supply that has 2 USB ports. This works quite nicely.
Could to try to just plug the lumacode into a composite input on a TV. This would show how the signal looks in B&W and if there is some instability issue at the side of the MARIAdigitizer.

My plan going forward is now to get to the bottom of the problems, fix them and have a new production run. Everyone who ordered on of the prototypes will get free replacements once this is sorted out.

Some other questions here:
Did you have to change anything on the horizontal timing (total pixels, horizontal offset) to get the picture correct?
Did you try a 2600 game on the machine? Any glitches there?
Do the newer games have specialized hardware in their cartdriges? Like sophisticated mappers such? Maybe these have different access timings so the MARIAdigitizer samples the incomming data at the wrong time. This would really be very hard to get right in all circumstances.

One more question: Would you be willing to set up a method to update your MARIAdigitizer with experimental firmware versions to get this working properly? You would need such a programmer for this and you need to solder pins to the JTAG header:
https://www.mouser.at/ProductDetail/Crowd-Supply/cs-tinyfpga-06?qs=vmHwEFxEFR8KFx9OtA%252Bpcw%3D%3D
Please mail me directly to fix the details on this (c0pperdragon50 at gmail.com)

[CrossBow777]

I will send you an email on this as one thing is very clear in my testing so far today. Part of the issue I'm seeing is because of the 7800GD cartridge. Using my Dragonfly cartridge, many of the issues are NOT happening. So I suspect it is a timing issue related to the 7800GD. I know that cartridge has a break out to menu function that is reading or lookin for joystick combos to bring up the on screen display to save states and such and that does cause issues with some games requiring that option to be disabled for those games. The Dragonfly literally mimics the actual cartridge to the 7800 so it is a more real world cartridge test scenario and in these instances the results are MUCH better overall.