Question: I'm a hardcore C64 artist. I'm used to games on C64 like "Io" with the best GFX available. I had a 1701 monitor, which had perfect video output. Does your hardware setup match? No lags in scrolling, fluid 50Hz all the time? No ghost colours, every single pixel clean and sharp, both in multicolor and highres? If you do RVS ON bulks on the screen with all the colors next to eachother you get evidence: they all must be pure without ghost coloring into eachother. And finally, the analog blur. I do NOT want digital razor sharp pixels that, but the original analog softness.
That "monochrome option" looks really sharp, and would be a good option for extended coding sessions on the C64. The"warmup session" is classic, man! Broke a sweat, did you? 😆
@@RetroHackShack Of course, I was replying to @cathydowns5442 when he/she said that the result is the same after and before the mod. Thanks for the reply Aaron! I really enjoy your videos
Now that this exists, it occurs to me that both the C128's A/V signals and the RGBI output could be sent to the same RGB2HDMI. The pi Hat would just need to be capable of accepting both signals. If it can do that, easily switching between the two might be possible as well. Imagine being able to have your 40 & 80 col sources coming out of the same RGB2HDMI device over a single HDMI cable.
C0pperdragon has a version for the VIC-20, too. Right now, he only has a PAL version, but I just sent him an NTSC 6560-101 so he can reverse engineer the signaling and get the NTSC version done. I get the first one off the line for loaning him the VIC, so I'll be showcasing that on my channel when he's done with it. 😁
Excellent product and video! Love your RGB2HDMI adapter, too. I will be showing/selling an adapter for Commodore PET that outputs HDMI at World of Commodore this December. It uses your board. So hopefully you will have lots in stock soon. Thanks for sharing
@@RetroHackShack Do you use Chinese products, or are all components you sell made in USA hopefully? I rather support US than that gruesome authoritarian regime "new world order" trying to control the world 😑
Not a fan of crocodile clips. The original Copperdragon mod was very good, probably the best quality output of any video mods. I like all these people stressing about "Ok Google".. 😂
i think the alligator clips are a bit thick too put under the case, there's that other kind that just clips the pins that take up less space (no idea what those are called), but then i guess you have to find an actual ground pin to clip to if you went that way. Anyway, can totally see why they used the alligator clips, they're cheap and easy for a novice to use, and people more experienced might just cut them off and can solder them in.... so a good option for everyone.
I have a NASTY idea, why don't use the colour bits to increase resolution? If Black is 0000 and Red is 0100 then we can use that to display Black-White Graphics through this adapter at 640x400 pixels. Or if this doesn't work out, buffer the signal like the Amiga 2024 display does, and then display the frames next to each other.
Thought a bit about it... using colour would be hard because you really have little control about colour on the C64 as you can not really change colour on every pixel however you want. But putting a screenbuffer in that chip that caches several screens and outputs them at higher resolution... that should be possible with this kind of hardware inbetween. So you could get 640x400 at 12,5hz/15hz or even 1280x800 at 3,125/3,75hz. Ok, the last one would be interesting because it would 132kByte of memory if used Hi-Res. But Text-Mode with 16kByte would be still fine.
I don't think you even need the ground wire. VIC-II and the "dizer" board should already be on the common ground with the RF socket. So, only the "live" wire connected should work the same.
Revelation! Will this work on the KU-14194HB breadbin? Can you connect power to the RB from the C64 board? Is this additional analog board necessary? Because on the Tindie website I only see VIC-II-dizer and RGBtoHDMI, can only these two boards be used without the analog board?
This all seems a touch crazy, in that your adding a computer (Raspberry Pi) with many times the compute power of the '64 just to generate colour video.
Sophia 2 (FPGA) on the Atari 8bit systems must also use the same protocol. On the other hand its emulates GTIA so you get to rest your old Chip.With a single cable mod you get the best things from both "worlds"...amazing sharp picture on a CRT screen.
Any chance you could show doing this mod to a Atari 130xe or 800xl? I just finished doing this mod to one of my breadbins and I must say the results are breathtaking! This is a game changer for those of us who dont have an old Monitor and are sick of the jail bars and noise on the screen from the alternatives. Thanks for doing this video and supplying the RGB2HDMI stuff. Will be ordering more for my other computers soon.
Great video, but it leaves me with some questions. Could the RGB2HDMI be tucked inside the C64 and the HDMI come out the User-Port or Cassette Port if you're not using them? And for Audio, how would I incorporate my Audio Embedder in this setup?
Cool video, though I do wish people giving commands to their Smart Home devices would mute the audio. Mine set up the timer, which I then had to cancel.
Question. With this solution, what is the best option for outputing sound? Use the Monitor out cable I suppose, but I am not sure how to get the sound to the hdmi signal for the tv? What are others doing to solve this?
Fortunately I live in France where TV have a scart connector. The circuitry inside the TV is as good as any one may install inside the C64. Just remove the rf modulator and install a dummy required filter
Haha, I can't wait to see how they figure out the LumiCode for the Apple II, based on what Dave Murray says has to happen in order to show all the colors on one of those, OMH!
Really cool… how about lag when this go through the raspberry pi? I have no clue how this works so excuse my maybe idiotic question. Do you have any lag then or how is this archived? Very cool challenge and great mod 🎉
I would prefer a switchable solution - does it affect the standard AV port's output, by the way? There was a bit of a creak when you lifted that VIC chip.
So two of my favorite computers are the Apple II(][ and //e specifically) and the Nintendo Family Computer(Famicom)… is there an option for at least the Apple II's??
@@RetroHackShack- It's a clever way of packing 4 bits for 16 colors encoded in voltage levels. However, without the RF connector patch, you could just snake an HDMI cable directly to the VIC-II/HDMI converter for simplicity. Yes, no, maybe?
But . . . the Commodore 64 was never intended to have pixel perfect graphics. ALL monitors at the time the machine was designed were CRT based, and the C64 was designed to use these.
Sound will have to come separately from the av connector. You could get a cheap HDMI combiner if you really wanted to. There is not an efficient way to combine it on the RGBtoHDMI.
@@RetroHackShackNot yet I hope. Would be a boon to make it more plug and play if you will. Neat little thing. Wondering if hiding the RGB2HDMI inside the box could be a thing as well. How well does it work with those mods that remove the RF box and replaces it with some small thing?
Would be cool with one package where you remove the whole RF part and replace with this. So everything is inside and you only have a HDMI out on the backside.
1337 thumbs up, you're welcome. ;) Under a minute, add a couple of minutes to unscrew all screws... "if this was a breadboard"? :D :D Is there a box for the lumacode to hdmi board? Loose boards hanging feels a bit "experimental".
I don't understand why Lumacode is required considering the comparators in the rgb2hdmi does the same thing. I suspect more is happening then just separating colour into a voltage code, like some sort of conversion.
I think in this case it has to do more with the speed of the cpld. It's the same reason this device can't handle color composite signals either. I think it would require a more expensive chip like a large FPGA.
where can I find the commodore 64 with the tape deck and floppy disk drive and some of the games I had? I wish I could remember the names of the games I had. Let me know.
@@RetroHackShack the 8 pin out to a video to VGA converter works. I have seen it done. I am just wondering if you could connect the output from the VGA converter to a vga to hdmi converter
Is it possible to skip the HDMI step and just have C64 to RGB? I have a Sony PVM monitor and currently connect my C64 via SVideo. I'd love to connect it to the RGB input instead!
Looks good but pricey if you don't have any of the parts. All in with shipping it is over $200. (RGB2Hdmi, Analog board, PiZero, VicDizer, cables, Shipping). Because I don't have any of these things I will just stick to my 1702 and Sony PVM. I have used other HDMI converters with varying success. Considering most of these parts are out of stock it is an easy decision. No offense intended and it looks like a great solution for people that already own a RGB2HDMI setup. However, people should know what this set up costs. You might as well buy a Retrotink 2x-pro and just plug into that.
"If this were a breadboard..."? What do you mean? How would there ever have been a "breadboarded" Commodore 64? Ha, come to think of it, that would be an interesting project; I hope you breadboard the chips and capacitors, etc. out sometime and make it run, just for the fun of it. But... what should that have to do with this video?
I ordered one and the PI shield that go's with it. It did not work, there is no luma coming out of the inter poser board. I messaged c0pperdragon and got a response but It got quiet after that. I send him al the scope data on every pin of the VIC, but still no reply. So I think that is something to be aware of before ordering on tindie. I really wanted this to work in my uni64 uBook.
"Don't do this at home, actually..." OK, then where do you think the best place for us to do this would be, and why would that place be the supposedly "better place"?
I don't want HDMI. It is useless. A C64 needs a screen of maby 30-50cm max. Never found a PAL screen with that size and HDMI. So we need RGB out. And we need a modded ROM to get rid of the unreadable purple on purple.
While you didn't cause a timer like you did for others, I'm unable to get past the point where you tell you Google to stop, it stops my video, when i hit play, it must have jumped back a fraction of a second and hitting play puts me back to you saying "ok Google, stop" in could be here a while. Lol
What about digitizing the audio into a SPDIF signal that will feed the HDMI encoder board that feed the HDMI signal to the TV so that you have sound and video.
Question: I'm a hardcore C64 artist. I'm used to games on C64 like "Io" with the best GFX available. I had a 1701 monitor, which had perfect video output. Does your hardware setup match? No lags in scrolling, fluid 50Hz all the time? No ghost colours, every single pixel clean and sharp, both in multicolor and highres? If you do RVS ON bulks on the screen with all the colors next to eachother you get evidence: they all must be pure without ghost coloring into eachother. And finally, the analog blur. I do NOT want digital razor sharp pixels that, but the original analog softness.
You totally started a timer on my Ok Google. 🤣
Ha ha. Sorry
he wanted folks at home to feel like they were included in the suspense 😀
Lol same for me
That "monochrome option" looks really sharp, and would be a good option for extended coding sessions on the C64.
The"warmup session" is classic, man! Broke a sweat, did you? 😆
Easy modification yet great result,
One thing I wish you did is to make a comparison screenshot for before and after.
Thanks Aaron!
before and after are the same...
@@cathydowns5442 What is the purpose then for this mod?
@ahmad-murery This mod enables you to connect the C64 to an HDMI display. I thought it would be obvious from the title of the video.
@@RetroHackShack Of course, I was replying to @cathydowns5442 when he/she said that the result is the same after and before the mod.
Thanks for the reply Aaron! I really enjoy your videos
The Commodore 64C is a great computer.
Yeah, I wouldn't trust those alligator clips to something I planned on screwing the case back together around. They're anything but permanent!
Now that this exists, it occurs to me that both the C128's A/V signals and the RGBI output could be sent to the same RGB2HDMI. The pi Hat would just need to be capable of accepting both signals. If it can do that, easily switching between the two might be possible as well. Imagine being able to have your 40 & 80 col sources coming out of the same RGB2HDMI device over a single HDMI cable.
C0pperdragon has a version for the VIC-20, too. Right now, he only has a PAL version, but I just sent him an NTSC 6560-101 so he can reverse engineer the signaling and get the NTSC version done. I get the first one off the line for loaning him the VIC, so I'll be showcasing that on my channel when he's done with it. 😁
Great job by all involved in this. Loved the 80s-style montage too.
Excellent product and video! Love your RGB2HDMI adapter, too. I will be showing/selling an adapter for Commodore PET that outputs HDMI at World of Commodore this December. It uses your board. So hopefully you will have lots in stock soon. Thanks for sharing
I have ordered more. Hopefully they will come in soon.
@@RetroHackShack Do you use Chinese products, or are all components you sell made in USA hopefully? I rather support US than that gruesome authoritarian regime "new world order" trying to control the world 😑
I think you cheated a little by not having to take the screws out first LOL
Well to be fair that's not a modification.
lol, I was thinking that as it usually takes me a minute just to open the case!
If you use old computers, in general you never have your screws in.
Thanks, I wasn't aware of these mods.
Not a fan of crocodile clips. The original Copperdragon mod was very good, probably the best quality output of any video mods. I like all these people stressing about "Ok Google".. 😂
Agreed. I would never use them personally, but they are a good option for those who can't solder.
i think the alligator clips are a bit thick too put under the case, there's that other kind that just clips the pins that take up less space (no idea what those are called), but then i guess you have to find an actual ground pin to clip to if you went that way. Anyway, can totally see why they used the alligator clips, they're cheap and easy for a novice to use, and people more experienced might just cut them off and can solder them in.... so a good option for everyone.
Sir, you are so much better than any Apple Bar Tender. I drink whatever you're mixing!
Wow, thanks!
Haha, not counting screw removal. But yeah, I like your dramatic music that went with that minute!
Thanks
@@RetroHackShack: You're welcome; happy Halloween! 🎃👻👹☠️😈
I have a NASTY idea, why don't use the colour bits to increase resolution? If Black is 0000 and Red is 0100 then we can use that to display Black-White Graphics through this adapter at 640x400 pixels. Or if this doesn't work out, buffer the signal like the Amiga 2024 display does, and then display the frames next to each other.
Thought a bit about it... using colour would be hard because you really have little control about colour on the C64 as you can not really change colour on every pixel however you want. But putting a screenbuffer in that chip that caches several screens and outputs them at higher resolution... that should be possible with this kind of hardware inbetween. So you could get 640x400 at 12,5hz/15hz or even 1280x800 at 3,125/3,75hz. Ok, the last one would be interesting because it would 132kByte of memory if used Hi-Res. But Text-Mode with 16kByte would be still fine.
Interesting upgrade! What is the latency introduced by VICII-dizer + RGBtoHDMI + HDMI itself?
Very low. I can't remember off the top of my head but it's something like a fraction of a frame.
And if you put a Pi into the process, you can as well run a C64 emulator on the Pi.
I don't think you even need the ground wire. VIC-II and the "dizer" board should already be on the common ground with the RF socket. So, only the "live" wire connected should work the same.
Revelation! Will this work on the KU-14194HB breadbin? Can you connect power to the RB from the C64 board? Is this additional analog board necessary? Because on the Tindie website I only see VIC-II-dizer and RGBtoHDMI, can only these two boards be used without the analog board?
You can pull power from the C64 if you are using the Zero. Larger Pis probably not. You do need the analog board.
This all seems a touch crazy, in that your adding a computer (Raspberry Pi) with many times the compute power of the '64 just to generate colour video.
Svideo is good enough.
Sophia 2 (FPGA) on the Atari 8bit systems must also use the same protocol. On the other hand its emulates GTIA so you get to rest your old Chip.With a single cable mod you get the best things from both "worlds"...amazing sharp picture on a CRT screen.
Awesome! - do you think there's any added latency?
(other than what's added by the monitor)
I'm assuming there isn't any reason you can't solder those wires to the RF instead of using clip leads.
Correct. They are meant to make it easier for people who don't like to solder.
Any chance you could show doing this mod to a Atari 130xe or 800xl?
I just finished doing this mod to one of my breadbins and I must say the results are breathtaking! This is a game changer for those of us who dont have an old Monitor and are sick of the jail bars and noise on the screen from the alternatives. Thanks for doing this video and supplying the RGB2HDMI stuff. Will be ordering more for my other computers soon.
I'm curious, what is this 'Analog Board' he is using with the RGB2HDMI & Rasp Pi Zero...??? Any help would really help. Many thanks... : )
Why is a GND wire required to the modulator? I guess it's connected to GND already anyway?
Does this work with the breadbin C64? Does it introduce much lag?
Sorry but "challenge" is also written with an "e" in French! 😄
Hahahahahahaha the workout was hilarius!!!! go on, one more rep!
It does count for 64 when using a real C64!!!
60seconds .....your awesome arron!!
Great video, but it leaves me with some questions.
Could the RGB2HDMI be tucked inside the C64 and the HDMI come out the User-Port or Cassette Port if you're not using them?
And for Audio, how would I incorporate my Audio Embedder in this setup?
If you are in this much of a hurry to get hdmi installed on a retro device, you have bigger issues you should worry about 😂
Exactly. Retro games and low potency marijuana belong in a slower frame-rated life, no matter how much it hertz.
Cool video, though I do wish people giving commands to their Smart Home devices would mute the audio. Mine set up the timer, which I then had to cancel.
Question. With this solution, what is the best option for outputing sound? Use the Monitor out cable I suppose, but I am not sure how to get the sound to the hdmi signal for the tv? What are others doing to solve this?
If you have no audio input on you monitor, you can buy a HDMI inserter/embedder. Or just use some powered speakers.
Love the videos... any chance you guys would be willing to take on an RGB to HDMI board for the Apple IIgs? :)
You hacked my phone! My phone set the same timer when you said "Google set a timer for 60 seconds.
Did it end at the same time?
@@RetroHackShack yup and my phone also responded when you said stop. I should make a short of it.
Love the warm-up sequence!
Thanks 😊
OK, so with the shield then there _still_ isn't soldering. But yeah, like I said, I would definitely replace the ali-clips with soldered connections.
Fortunately I live in France where TV have a scart connector. The circuitry inside the TV is as good as any one may install inside the C64. Just remove the rf modulator and install a dummy required filter
Haha, I can't wait to see how they figure out the LumiCode for the Apple II, based on what Dave Murray says has to happen in order to show all the colors on one of those, OMH!
Seems to be not a big deal. Just a small finite state machine implemented in FPGA, and voila, the NTSC color encoding becomes a Lunacode.
You can already get this with just the RGBTOHDMI and the analog board. Handles NTSC artifacting perfectly.
Fantastic! Thank you!
The warm-up montage was Gold!!!
Rofl, my google nexus reacted on your ok google command and did set a timer😂
Sorry. I need to edit that out for next time.
Does it work on older c64 motherboards?
Should the old RF modulator still be in ? Because I removed it already.
Not necessarily. It won't be used anymore anyway unless you wanted to for some reason.
Nice and easy Mod, does this work on the ViC20 as well?
Really cool… how about lag when this go through the raspberry pi? I have no clue how this works so excuse my maybe idiotic question. Do you have any lag then or how is this archived? Very cool challenge and great mod 🎉
It is very low. Like a fraction of a frame.
You fiddled a while with desocketing the vic. Could have shaved a couple of seconds there 😉
Hoping a CoCo version comes out some day.
Does this work with both PAL and NTSC?
Next time.... warm up with a C64 in each hand, then maybe you can do it in 30 seconds! ;)
I'm just glad I wasn't installing it in a PET.
I would prefer a switchable solution - does it affect the standard AV port's output, by the way?
There was a bit of a creak when you lifted that VIC chip.
The AV port still works just fine
So two of my favorite computers are the Apple II(][ and //e specifically) and the Nintendo Family Computer(Famicom)… is there an option for at least the Apple II's??
What about the latency and will there be a solution for the C128 ?
Shame Pi cant be fitted internally too so still an all in one unit
Personal preference, but I like that I can use one Pi and move it from system to system.
Will this work alongside the c0pperdragon RF Modulator replacement board if I just connect the output directly to a normal RF socket?
Yeah. I suppose so. Just connect it directly to the rca signal pin and bypass the rest.
@@RetroHackShack Thank you.
Hi, any idea when you will have the RGBtoHDMI boards available again?
Next week I think.
@@RetroHackShack- It's a clever way of packing 4 bits for 16 colors encoded in voltage levels. However, without the RF connector patch, you could just snake an HDMI cable directly to the VIC-II/HDMI converter for simplicity. Yes, no, maybe?
@RetroHackShack -
Does this work on only the NTSC machines, or will it work on the PAL models as well?
TIA!
Yes. PAL as well.
Do that exercise montage using an SX-64 next time! 😰 BTW, will this mod work on an SX-64? How about a C128?
Yes for both, but you will need a different dizer board for the C128.
Super fast but not really very elegant. Thanks for the video!
But . . . the Commodore 64 was never intended to have pixel perfect graphics.
ALL monitors at the time the machine was designed were CRT based, and the C64 was designed to use these.
Btw....any retro hobbyist who respects himself never keeps RF shielding or case screws on his machines....so your scenario is real life accurate.
How do you not get 16:9 and go back to 4:3?
impressive! - and what about sound?
Sound will have to come separately from the av connector. You could get a cheap HDMI combiner if you really wanted to. There is not an efficient way to combine it on the RGBtoHDMI.
@@RetroHackShackNot yet I hope. Would be a boon to make it more plug and play if you will.
Neat little thing. Wondering if hiding the RGB2HDMI inside the box could be a thing as well. How well does it work with those mods that remove the RF box and replaces it with some small thing?
Would be cool with one package where you remove the whole RF part and replace with this. So everything is inside and you only have a HDMI out on the backside.
1337 thumbs up, you're welcome. ;)
Under a minute, add a couple of minutes to unscrew all screws...
"if this was a breadboard"? :D :D
Is there a box for the lumacode to hdmi board? Loose boards hanging feels a bit "experimental".
Wow! He did it!🥳🎉
I don't understand why Lumacode is required considering the comparators in the rgb2hdmi does the same thing. I suspect more is happening then just separating colour into a voltage code, like some sort of conversion.
I think in this case it has to do more with the speed of the cpld. It's the same reason this device can't handle color composite signals either. I think it would require a more expensive chip like a large FPGA.
It sound like this completely replaces the Vic II as long as you don't need the luma/chroma output. Is this true?
where can I find the commodore 64 with the tape deck and floppy disk drive and some of the games I had? I wish I could remember the names of the games I had. Let me know.
Can I use the 8 pin out to a video to vga converter then go to a vga to HDMI converter?
No. I don't think so.
@@RetroHackShack the 8 pin out to a video to VGA converter works. I have seen it done. I am just wondering if you could connect the output from the VGA converter to a vga to hdmi converter
Does this work on the older C65 which has a 5 pin RF cable?
Yes
Is it possible to skip the HDMI step and just have C64 to RGB? I have a Sony PVM monitor and currently connect my C64 via SVideo. I'd love to connect it to the RGB input instead!
Not with this particular mod.
Looks good but pricey if you don't have any of the parts. All in with shipping it is over $200. (RGB2Hdmi, Analog board, PiZero, VicDizer, cables, Shipping). Because I don't have any of these things I will just stick to my 1702 and Sony PVM. I have used other HDMI converters with varying success. Considering most of these parts are out of stock it is an easy decision. No offense intended and it looks like a great solution for people that already own a RGB2HDMI setup. However, people should know what this set up costs. You might as well buy a Retrotink 2x-pro and just plug into that.
Nothing wrong with a good ole CRT if you have one.
this is a very expensive solution, and closed source
Does sound pass through the hdmi or do you need to attach speakers?
I'd like to know as well :) I didn't read anything about audio on C0pperdragon's site either.
No. Sound has to be passed through separately. I usually grab it from the eight pin video din.
Good. I thought maybe the 8 pin might not work when video signal is coming through other connection
I'm not doing this if it's going to void my warranty.
Look at you, showing that your not cheating by making everyone's google device set a timer for you.
"If this were a breadboard..."? What do you mean? How would there ever have been a "breadboarded" Commodore 64?
Ha, come to think of it, that would be an interesting project; I hope you breadboard the chips and capacitors, etc. out sometime and make it run, just for the fun of it. But... what should that have to do with this video?
I ordered one and the PI shield that go's with it. It did not work, there is no luma coming out of the inter poser board. I messaged c0pperdragon and got a response but It got quiet after that. I send him al the scope data on every pin of the VIC, but still no reply. So I think that is something to be aware of before ordering on tindie. I really wanted this to work in my uni64 uBook.
Please keep us posted. Definitely not gonna purchase if there's no customer support.
I will@@Mario00064
That's odd. I never had a problem even before I started doing videos.
Small update, I got send another board and this one works. And it also works in the uni64 uBook clone!
I’m sorry, but it doesn’t look like a simple mod. I think we have a different idea of what is simple.
can you boost a bit these washed C64 colors to be more saturated, more exciting and more eye-catching? Cheers!
Yeah. I think the palette is adjustable.
Where on your website are these boards for sale???
Where do we get the analog board? 3:26
Link is in the description. Choose RGBtoHDMI then choose Analog Board from the drop-down box.
@@RetroHackShack thanks!
Do you also get the audio through the HDMI?
No. Audio has to be passed separately or you can use an HDMI combiner.
Is there any lag with this mod ?
No
Who else had Google respond and set a timer during the video?! Lol
"Don't do this at home, actually..."
OK, then where do you think the best place for us to do this would be, and why would that place be the supposedly "better place"?
Nice hack.
❤
The tender site is down 😞
I don't want HDMI. It is useless. A C64 needs a screen of maby 30-50cm max. Never found a PAL screen with that size and HDMI. So we need RGB out. And we need a modded ROM to get rid of the unreadable purple on purple.
Over $100 no you won't see a lot more.
Why would there need to be a different version of this for each major VIC-II computer model series?
60 seconds but the video is 15 minutes?
While you didn't cause a timer like you did for others, I'm unable to get past the point where you tell you Google to stop, it stops my video, when i hit play, it must have jumped back a fraction of a second and hitting play puts me back to you saying "ok Google, stop" in could be here a while. Lol
What about digitizing the audio into a SPDIF signal that will feed the HDMI encoder board that feed the HDMI signal to the TV so that you have sound and video.
Unfortunately, that is really resource intensive. The cheapest way is to buy an HDMI combiner.
*Challenge ;)
What a cheat, removing all screws and covers before you started , shame on you,