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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Fri Aug 24, 2018 3:35 pm 



Joined: 08 Mar 2017
Posts: 430
First decide on how you want to power the Arduino. You have an extra power supply, so best if you use that.
Disconnect any Vcc wires you may have on the Arduino. Just keep the ground wire, SDA + SCL and debug wires.
Then power the GBS and Arduino separately.

Next, please verify that the RGB input is 0.7Vpp and AC coupled from the Supergun.
This may be called "TV ready" or similar, and specifically not "arcade monitor" (since those use way higher signal levels).

Now you should have stable sync (no more dots appearing in the console).
Commands are listed in the sketch, in a huge switch-case starting at line 2346.

Also, look for an ESP8266 board soon. Arduino won't be supported much longer. It's now limiting what I can do with the project.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Fri Aug 24, 2018 3:53 pm 


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rama wrote:
First decide on how you want to power the Arduino. You have an extra power supply, so best if you use that.
Disconnect any Vcc wires you may have on the Arduino. Just keep the ground wire, SDA + SCL and debug wires.
Then power the GBS and Arduino separately.

Next, please verify that the RGB input is 0.7Vpp and AC coupled from the Supergun.
This may be called "TV ready" or similar, and specifically not "arcade monitor" (since those use way higher signal levels).

Now you should have stable sync (no more dots appearing in the console).
Commands are listed in the sketch, in a huge switch-case starting at line 2346.

Also, look for an ESP8266 board soon. Arduino won't be supported much longer. It's now limiting what I can do with the project.


Ok, thank you sir! Is there a "best order" of powering the units? I.E. Arduino first, wait 10 seconds, then power the GBS, or something like that?

I have pinged arcadeforge to see if they can provide insight on the RGBS output from the Mak Strike. No scope here...yet... :( If anybody knows or has the ability to verify this with their own equipment, any help is appreciated.

I will power both boards externally, as you've suggested. Given USB is capable of powering both boards, is there any harm in having USB connected to the arduino and external power connected to both boards?

I will check out the commands, and play around with it some more tonight. Had to run off to work after getting this far. :/

And, I saw that arduino is reaching end of life in this project. Just wanted to get something up and running to fiddle around with, but I will look for and ESP board.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Fri Aug 24, 2018 6:40 pm 



Joined: 08 Mar 2017
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I wouldn't worry about the order too much, but it works well if both are powered on at the same time.
If the Arduino is too far ahead (early), it won't get to initialize I2C, and an Arduino reset is necessary.

USB from a common port delivers a maximum of 500mA, too little for both boards!
The GBS should have its own 5V+ / 1A supply. More amperes preferred, as the 5V / 1A supplies often are on the cheap side.
If you use a 7V to 12V supply (ideally 8V), you can use the same supply for both boards.

(Arduino runs at 5V internally, so the external supply needs to be a little higher than that. The GBS runs at 3.3V internally.
It's okay to let the Arduino handle I2C and the debug wire, event hough it runs at a higher voltage. This is because the Arduino never drives an output in gbs-control.)

In case USB and an external supply are connected, the Arduino has a protection circuit that allows only one source.
Most ESP8266 dev boards should have something similar.

Edit:
I noticed very long wires in your build. I would place the GBS much closer to the supergun, if that's possible.
You want the RGB input wires and the I2C + debug wires as short as reasonably possible.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Fri Aug 24, 2018 7:35 pm 


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rama wrote:
I wouldn't worry about the order too much, but it works well if both are powered on at the same time.
If the Arduino is too far ahead (early), it won't get to initialize I2C, and an Arduino reset is necessary.

USB from a common port delivers a maximum of 500mA, too little for both boards!
The GBS should have its own 5V+ / 1A supply. More amperes preferred, as the 5V / 1A supplies often are on the cheap side.
If you use a 7V to 12V supply (ideally 8V), you can use the same supply for both boards.

(Arduino runs at 5V internally, so the external supply needs to be a little higher than that. The GBS runs at 3.3V internally.
It's okay to let the Arduino handle I2C and the debug wire, event hough it runs at a higher voltage. This is because the Arduino never drives an output in gbs-control.)

In case USB and an external supply are connected, the Arduino has a protection circuit that allows only one source.
Most ESP8266 dev boards should have something similar.

Edit:
I noticed very long wires in your build. I would place the GBS much closer to the supergun, if that's possible.
You want the RGB input wires and the I2C + debug wires as short as reasonably possible.

Thanks again for more good advice. :)

The GBS is powered off of the arcade power supply @ 5V, so there *should* be plenty of ampacity available there. The barrel plug measures around 5.25V when it is unplugged from the GBS, and while the supergun readout simultaneously displays 5.00V under load.

Got a ESP82 on order, so I will continue fiddling around with this current setup until that shows up.

I knew the long wires might be an issue, but as you can see, my "mobile" setup there is limited on real estate. If I remove the SF2 board and plug in a CPS2 game, for instance, there's less available work space. I'm sure I can figure something out and secure the arduino (and later ESP82) close to the GBS tho, once I get things dialed in.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Fri Aug 24, 2018 10:03 pm 



Joined: 08 Mar 2017
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Short cables are just a general design goal to keep in mind.
An alternative is diy coax for each RGB line, or a short, proper VGA cable.
You just want to avoid long stretches of unshielded RGB, since it will pick up noise easily.

The I2C wires are fine at current length.
You'll notice when they get too long by either no operation, or by seeing I2C errors while in operation.
(There is one I2C recover step in setup(), that sometimes triggers. That one is unrelated ;) )

Your boards 5V is regulated, right?
You could use it to power the Arduino directly (bypassing the voltage regulator).
The pin is commonly called "5V" on Arduino.
This way, you don't need any extra supplies, because:
- the GBS can use its voltage regulator to step 5V down to 3.3V
- the Arduino gets the required 5V, which wouldn't be possible if you fed 5V into the "Vin" pin, since Vin needs to be ~2V higher than Vout


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Fri Aug 24, 2018 10:25 pm 


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rama wrote:
Your boards 5V is regulated, right?
You could use it to power the Arduino directly (bypassing the voltage regulator).
The pin is commonly called "5V" on Arduino.
This way, you don't need any extra supplies, because:
- the GBS can use its voltage regulator to step 5V down to 3.3V
- the Arduino gets the required 5V, which wouldn't be possible if you fed 5V into the "Vin" pin, since Vin needs to be ~2V higher than Vout


Okay, that's good info. I read multiple places "DO NOT PROVIDE THE ARDUINO WITH INPUT POWER ANYWERE EXCEPT VIN!", so I was avoiding that like the plague.

I was daisy-chaining the arduino off of the GBS, but at Vin. However I was getting nothing from the GBS. Is it possibly because the voltage was being stepped down too much from the GBS?

Although, separately powering the arduino with a 5.2V 1A rated raspi power supply, via the arduino's barrel plug, it was doing the same thing. In this configuraiton, however, the raspi power supply kicks on 2-3 seconds after supplying power, so the GBS would be on before the arduino. Possibly separate issues producing seemlingly the same result?

The HAPP arcade power supply in the pictures is regulated and adjustable. Any reason for concern, for either the arduino or the GBS, if input is around 5.25V at the GBS? That's where it was at, (albeit not under load) with the supergun showing 5.00V on the dot, and I don't want to power the arcade board with less than that.

:edit: I just re-read your previous post, and see that there might be an issue at the RGB lines. :headslap: I've got some 75ohm coax, but it is truly a pain to work with. What about some shielded cat5/6 cable? I hope that's not a dumb question, but that stuff is easy to work with and I've got plenty of spare cat cables lying around that I would have no problem chopping up.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Sat Aug 25, 2018 12:32 am 


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Don't worry about coax over that short run it won't change a thing.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Sat Aug 25, 2018 3:17 am 


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Syntax wrote:
Don't worry about coax over that short run it won't change a thing.

Thanks for that!

Well, I"m happy to report success. I relocated the GBS. Didn't shorten the RGB wires at all, but I think with them not traveling past the surge protector, it fixed the interference. That seems the most likely culprit to me, at least.

I also am powering both boards with their own external power sourced. Connected only SCL, SDA, ground adn debug between the 2.

I also soldered back in some color pots. But, these came off a retroelektronic supergun that I fried a couple weeks back. These RE pots have a range up to 560ohm. The stock ones have a range up to 450 ohm. These pots are all centered, and the colors look good.

I haven't tried sending commands yet, and as you can see, the geometry is off, but I was excited it fired up so easily and without much further direct involvement.

Oh, also, no noticeable lag. That's always a bonus. :)

I'll clean things up a bit once I get the ESP82. Next stop: pumping this into the OSSC and seeing how it looks. :D

Again, big thanks rama, and those whose work was the foundation for this great project.

:edit: I took a couple quick captures of Street Fighter titles: https://www.youtube.com/watch?v=C5pHK9j73ho

Spoiler: show
Image
Image
Image
Image


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Sat Aug 25, 2018 3:56 pm 



Joined: 08 Mar 2017
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Many thanks for the nice video and also your effort on the description for it!

A couple things I noticed:
There is no tear line, so you probably had FrameTime Lock enabled. Is that right?
If so, did you noticed the OSSC or capture card dropping any frames?
The OSSC may or may not switch between 1000 and 1001 lines, since that is what the "active" part of FrameTime Lock does.

When adding a line, the draw time for the entire frame is a little longer. This allows the source to catch up to the drawn frame.
Once gbs-control detects the source is past a certain point, the extra line is removed again.
This back and forth between just a little too fast, and just a little too slow is what allows the tear line to be out of picture all the time.
It's a great trick that bkoropoff came up with.
The issue is of course that the display has to accept this change. It is pretty significant in TV timing scales, but for some reason it seems to be very compatible.
It probably helps a lot that the switch is always done very briefly after VSYNC, so that there is a lot of time until the extra line is encountered.

Colors:
The colors seem a little dull in the video. This may still be an issue with the supergun, and the potentiometer fix you did for it.
Once you have the ESP8266, the web interface for gbs-control has an ADC gain feature.
You can remove the pots and use that gain to attenuate colors for maximum brightness without clipping ;)


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Sat Aug 25, 2018 4:23 pm 


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So far, I've just been running it at whatever it comes up at automatically, which I assume is the default NTSC profile. I need to get a USB extension cable in order to be able to reach the arduino from my desktop. Either my usb cable comes short or my vga cable comes short. I'll probably just be lazy about this until the ESP82 comes in. :oops:

I didn't notice any choppiness or dropped frames on the TV. Something in my capture setup tends to be a bit choppy. Very minimally, probably not noticeable to most people, but I notice it. It's consistently inconsistent via the Elgato Camlink, and across all sources, so that's where I'm currently placing blame. It doesn't happen with my older avermedia c127 pci-e capture card. But in this video (all captured via camlink), I don't see it really happening. So, I think the compatibility between GBS8200 and OSSC is very good.

Yes, agreed, the colors are a bit dull. I was actually getting some noticeable waviness in the picture and jailbars, with the colors a bit brighter. Probably need to do some tidying on that wiring sooner rather than later. Will play around with and without pots once the ESP82 shows up. :)


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Sat Aug 25, 2018 9:01 pm 


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Well, I'm not known for my patience. Went and got a USB extension cable. Playing around with sending commands to the arduino now. I am testing on the Samsung SyncMaster currently. When I send 'Y' for NTSC 240p, I get 960p. I assumed that's the default startup mode, at least for when it's a 240p(ish) source. Testing with a Street Fighter 2 Hyper Fighting board currently. When I send '9', I get 640x480.

640x480 looks better to me, so I'm getting it centered, but with a little bit of border around it. Sending commands for scaling horizontally and vertically (z, h, 4, 5) don't seem to do anything.

I also forcing 720p, but the image would scroll every second or so. The monitor was asking if it's HD, and said to try SD.

Lastly, how can I save the settings, once I get them dialed in.

Anything else you would like to see tested, rama?

Spoiler: show
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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Sun Aug 26, 2018 12:38 am 



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'Y' is actually 1280x720 with 750 lines of active video (standard).
'e' will get you the default 1280x960 / 1000 line preset.

All 3 presets emphasize a different work mode.
The 640x preset disables the scaling engine, since the combination of display clock and H-PLL range fit nicely to fill the picture.
It can look great on many retro sources but this relies on good processing on the target display.
Scaling doesn't work, well, because the scaling engine is disabled ;p

The 720p preset is like the default preset, except that it uses the maximum reasonable H-PLL frequency.
It has the least jailbar artefacts and works very well (at least here ;p).

Well, and the default preset is made to be compatible and look nice enough.

On Arduino, there is no preset saving.
This is only implemented on ESP8266, which has a big, easy to use storage via the SPIFFS file system.
Arduino could save settings in EEPROM, but I don't plan to implement it, as the necessary code would be too big for the program space.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Mon Aug 27, 2018 5:19 pm 



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Hi, I'm curious, how good will the GBS (with gbs-control) handle Amiga 15kHz interlaced signals? Will it deinterlace/flicker-fix nicely? Typically PAL: High res 640x512 laced, visible size 720 x 566 with overscan. My monitor Benq BL912 syncs great with the non-laced 15kHz 50Hz signals (typically games) using a simple RGB->VGA adapter, but flickers a lot in laced modes which is the mode I wanna use when doing simple wb stuff.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Mon Aug 27, 2018 9:00 pm 



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Interlace will flicker quite a bit. It's okay in 60Hz imo, but PAL will be an eye strain.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Mon Aug 27, 2018 9:47 pm 


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I don't know much about the deinterlace feature but I do know gbs does a better job than the ossc with Tekken ps1.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 9:27 am 



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rama wrote:
Interlace will flicker quite a bit. It's okay in 60Hz imo, but PAL will be an eye strain.


Thanks for the info. I'm currently using a cheap scart->hdmi converter with a hdmi->dvi-d cable to the monitor when running wb in interlaced mode. It works okay with deinterlacing, no flicker, but has some noise in the picture, also it is kind of a drag having to plug/unplug db23 and switch input sources on monitor. Had hopes of the gbs being a good cheap all-in-one solution using only vga to monitor but I guess it isn't that easy then.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 2:55 pm 


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So, I got a respsonse from arcadeforge, as to the composition of the RGB output from the Mak Strike.

My question was: Is it 0.7Vpp and AC coupled?

The answer I received: we just put resistors for sync and switch mode. RGB has a 1k Pot and can be regulated. AV Mode and 4:3 is set.

I asked what the rating of the resistors is, and what "AV Mode and 4:3 is set" means. Not sure how this may influence the output of the GBS, but hopefully arcadeforge can provide a little bit more color.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 3:37 pm 



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jbilander:
If you're okay with the generic scaler, then by all means try gbs-control.
Even if the deinterlacing isn't the best, the other benefits will make up for it ;)

NoAffinity:
Okay, that tells me a little.
It's probably not AC coupled and the level is not normalized to 0.7Vpp.
You're supposed to dial in your preferred brightness by using the pots on the supergun.

The AC coupling (using 220uF or more e-caps) is not strictly necessary.
It depends on the source amplifier design and the target input stage.
The GBS AC couples directly before the signals enter the IC, so it is protected in all cases.

I would just get a test picture from any of those arcade games test modes and then adjust the potentiometers for maximum brightness without clipping.
It won't be exactly 0.7Vpp, but then again, nothing really is with these retro machines.
(Early SNES often output 0.5Vpp or so, giving a very dull look.)

Edit:
"AV Mode and 4:3 is set" << These are SCART options. They're set to signal 4:3 instead of 16:9 and I suppose he meant to say "RGB mode" instead of AV (Composite Video).


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 4:41 pm 



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rama wrote:
jbilander:
If you're okay with the generic scaler, then by all means try gbs-control.
Even if the deinterlacing isn't the best, the other benefits will make up for it ;)


I might try it out, I like modding things but haven't bought a gbs-board yet though. :oops: What I'm after is a better workbench screen/picture in interlaced mode 640x512 and of course flicker-free. Games and demos on the Amiga often runs in lower res non-laced and they look very good on my benq-monitor with only using the RGB->VGA adapter, so I don't really need the gbs for that. Regarding the new bypass mode, will that effectively be like using the adapter just passing through the signals?


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 5:39 pm 



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Effectively, yes. Bypass mode always adds an ADC > DAC conversion, but at pretty good quality.
Sync signals are copies of the input, at 3.3Vpp.

The GBS mostly gives you more options.
I found that I can bypass many retro console signals directly to my monitor, but it never looks as good as the upscaled versions.
And since upscaling is more or less lag free, I'll use that ;p


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 6:16 pm 


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Thanks for the analysis, rama! I posted this information on another thread I have going about the Mak Strike, as well, and posed a question about how the OSSC handles the output from the Mak Strike, particularly in 4x and 5x modes. That question didn't seem appropriate here, but maybe you also have insight on that. https://shmups.system11.org/viewtopic.php?f=6&t=63020&p=1331937#p1331937 :)

Now, back to the subject at hand. Given the information from arcadeforge, do you still recommend doing the following?
Quote:
Every GBS board requires an additional 100 Ohm resistor on Sync-in to ground if you want to use the RGBS input.


And, are you saying the pots should remain on the GBS, even once I get the ESP82 in place?


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Tue Aug 28, 2018 8:26 pm 



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rama:

Sounds great, good work :D
Regarding the deinterlacing, will it be worse or similar to the stock fw with gbs-control? Looking at this youtube video, link below, I think it looks acceptable although some ghosting around the mouse pointer. 9:09 into the clip. Don't know if that is a 50 to 60 Hz conversion.

https://www.youtube.com/watch?v=q3J4QJsn0ig&t=549s


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Wed Aug 29, 2018 6:59 am 



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jbilander:
The stock firmware does 2 frame deinterlacing using a couple of video (movie) optimized algorithms.
It is flicker free but produces some artefacts, like the mouse cursor shows.

My firmware doesn't treat interlaced sources any different than progressive, so the only deinterlacing is from line doubling + scaling.
It has more flicker, exactly the type you would have seen on a CRT screen back then, but no extra lag or artifacts.
In addition, it takes care of all issues that were mentioned in that video.
Honestly, it's too bad that none of the youtube people ever want to test gbs-control.

NoAffinity:
I still don't know what the sync signal looks like. It's probably meant for TV, so yes, do use the 100 Ohm resistor.

You can leave the pots on the GBS if you want. Removing them is just a slight improvement over having them installed, but dialed all the way to the left.
If you measure DC resistance with a multi meter, you should see about 65 Ohm to ground on all 3 channels with the pots installed.
It will be 75 Ohms with them removed (the ideal value for TV level RGB).


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Wed Aug 29, 2018 9:30 am 



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Thank you rama for that great explanation. I totally agree, it would be very nice to see a review of this board modded and with gbs-control on it, to show what this board really is capable of with your custom fw controlling it.

Any plans on implementing 2 frame deinterlacing as an option in the future? I know it is probably a lot of work but just wanna hear your thoughts about it. If those algorithms are publicly available. I don't mind a little lag and the mouse cursor artifacts when running wb but can't stand the flicker. I think that would be the optimal cheap solution/compromise for Amiga users being able to run wb in 640x512 flicker-free for doing simple wb stuff having some more real estate to work with and then when gaming etc. either use your bypass mode or line doubling + scaling with almost zero lag and a quality picture, not to mention the convenience of everything running through the same vga port.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Wed Aug 29, 2018 10:19 am 



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Im now interested in hdmi option.
Wonder if its better to convert vga to hdmi
Or use hdmi version board.
What if we want scanlines but not seperate scanline generator. Does hdmi version work like vga and just has vga hdmi converter onboard or it's in logic level from chip to encoder conversion


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Wed Aug 29, 2018 7:54 pm 



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@jbilander
Others asked for that as well. Besides Amiga / old computers, it largely affects the PS2 library as well.
The issue I have is my limited development time.
This feature requires that I understand how the chip divides up the memory regions, how the Input Formatter interprets the signal, how the deinterlacer then works on it, and finally, how the image data is shuffled around the chip.
All these things interact, and there is no guide that explains any of this in sufficient detail.
Also, I fear that I'll run into ressource issues that require me to lower the image quality.

It'll be a lot of investigation again and I will probably get to it some day, but for the moment I want to focus on getting low res right.
The web ui should be a lot better as well, and format switching can (hopefully) be optimized to be even quicker.

@redcatex
The HDMI board is good, but comparatively expensive for the GBS (at $35 :p ).
It just adds an HDMI transcoder chip that converts what the GBA outputs (VGA) to HDMI.
While not fully digital, this still avoids that the scaler chip has to drive the VGA cable.
The quality is good. I get a little more consistent results than with pure VGA.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Wed Aug 29, 2018 8:17 pm 



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I might look into changing over to an HDMI board if the result is a little better. I really don't "need" to use VGA. My projector probably works better with an HDMI signal anyway.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Wed Aug 29, 2018 10:32 pm 



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VGA to HDMI dongles are another option.
They're probably all using the same transcoder chipset, likely the same that's on GBS HDMI boards.
(Would be great to know what chip that is, and have tech docs on it!)

A nice extra of dongles is that they often come with an audio solution as well.


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Thu Aug 30, 2018 12:29 am 



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oh crap I forgot about that!, although for me, it's not a problem as I have my audio routed externally to my sound system. I could see it being an issue for someone simply connecting the GBS to their TV though...


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 Post subject: Re: GBS 8200/8220 CFW Project
PostPosted: Thu Aug 30, 2018 12:30 pm 



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rama wrote:
@jbilander
and there is no guide that explains any of this in sufficient detail.


Thanks rama, I understand it is quite an effort to get deinterlacing working especially with limited documentation and time. You have those two docs, right?

TV5725 Registers Definition
https://drive.google.com/file/d/0B9y2RH ... lDdUU/view

5725 Programming Guide
https://drive.google.com/file/d/0B9y2RH ... BKNFk/view


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