I have no love for the look of the original screen.... the upgrade to the color LCD is perfect. Making old tech better is not necessarily a bad thing. It looks great. It's a wonderful solution. Good Job!
The original LCD was kinda green background with black pattern. Yours is black background with green pattern. At 14:24 underneath "Output Color" there is an "Invert"-option. Maybe this flips the color like it should be.
That might make it closer, you're right. But the original LCD was MDA with CGA emulation. So it actually was using dithering patterns to simulate different CGA colors (look at the pink of the Prince's skin on CGA, that becomes a dithered pattern on the original). So there's more to it, that's what makes me think it's not a matter of just using a different palette.
The biggest problem I had with the LCD was the lack of backlight. Changing the colour pallette file to make it more the light green on dark green might make it more authentic, while still having the advantage of a backlight. Although the advantage of having colour far outweighs any authenticity argument in my book! If I ever find my PPC I am strongly considering this mod, as it will make a great serial terminal for my retro computer projects!
Great video as always Noel! That's a very nice PC at the 10:23 mark 😉 I really should get back on to my Amstrad PC1512 video project, the RGBtoHDMI would make what I'm trying to achieve so much easier. I really appreciate this very thorough investigation, I think it's answered all of my questions (and a few I didn't realise I had!)
It is indeed a VERY nice PC. At some point I'd love to have enough space to get a classic one like that. Life goals 😃 Glad the video helped. I keep saying it, but RGB to HDMI is really impressive, and I think it's a fantastic fit for CGA video. I don't remember who first pointed it out to me, but it was someone on Discord. At first I almost dismissed it because "it had a Raspberry Pi" and I don't like overkill, but it's proven to be awesome!
I may have seen it before somewhere but seeing it in action, I learned from this video of yours such a thing as those super flat ribbon HDMI cables actually exists. Thanks for sharing those informations, it's one interesting project to follow.
If you would rather not see the rainbow pattern generated by the Pi on start-up, that can actually be disabled. You'd need to add "disable_splash=1" to config.txt which can be found in the SD card's root directory. The screen will simply remain black until the RGBtoHDMI kicks on. The screen mode info displayed on boot by the RGBtoHDMI software had been a bit of a pet peeve of mine, so thanks to your video I now know that that function can be disabled. I use this solution on an Amiga 500 which worked out of the box so never actually checked the menu options to see if it could be done... *d'oh*... Powerup Message disabled now as well here. Turning off the rainbow splash and info overlay has made this a completely seamless and fully integrated solution. Love your channel, keep them comming :)
Ooh, I didn't know that! I'll definitely do it. So that's great, I learned that trick from you and you learned the power up message. Between the two of us: Perfect silent booting. Yes! 😃👍
Yes, seriously! I played a lot of Quake with 250ms lag! Then I would go into campus and play from the machines there with 10ms lag and people would call me an LPB 😃
Great video Noel! But don't forget to make a second version at some point in the future to cover a possible video upgrade to VGA, as some users and me have proposed you in the past. ;-)
@@NoelsRetroLab I will look forward anxiously for this video! :-D Don't forget to add sound to complete your computer. Perhaps with some type of internal speakers? ;-)
The new HDMi cable is perfect. BTW, that is not laggy. My Speccy's plugged into the composit in on a freeview box, then into my TV through HDMI. It's 1/2 a second from keyboard click to the screen displaying what you pressed. Playing games on it is fun. LOL.
I don't know why anyone would want to use that. Then again I don't get why people want CRTs. Even when I was a kid I was like these things suck I hope we come up with something better soon. I saw a video by mattKC repairing a gameboy with a wierd pattern in the LCD among other problems (the switch was bad) He actually tried to fix the screen. I'm like WHY!?!?!? Just get a modern gameboy replacement screen kit. The hard parts are already solved all you have to do is swap it out and plug in a ribbon cable. Then you get a nice backlight. Some of them even have a way of getting color out of GB Color enhanced games. I have no idea how that works, but it's a thing. lol I'm far more interested in the actual machines than the accessories such as monitors and disk drives. I honestly don't ever want to use magnetic media ever again. lol
I am very interested in this. These days in retro community, whenever someone comes up with a good design, it becomes a commercial product to sell. It really feels like a big breath of fresh air to see such a good idea as an open source project! I will be building a Superfo Harlequin 128 v4A in near future, and it outputs RGB. I don't have a monitor that has an RGB input, the only screen I have that would work with the Harlequin is the house TV with its SCART input Unfortunately my better half doesn't like my toys around the house, out of the man cave. I have a lot of old VGA monitors, and I use one of them with a ZX-VGA-Joy on my 48K Spectrum. I believe this device does not output VGA, but as far as I know HDMI to VGA conversion is quite good with the cheap Chinese converters. I am torn between buying another ZX-VGA-Joy, or building this and using it with a HDMI-VGA converter. I really prefer to use my old monitors with my retro computers because of the 4:3 aspect ratio, I could get a new HDMI capable monitor, but they are all wide screen and I hate that look.
Yes, it's nice to see it not being commercialized to death like a lot of projects in a certain retro computer... If you have a lot of VGA monitors, maybe one of them accepts 15KHz signals and you can feed it the Spectrum one directly (once you combine intensity). Alternatively, swap out one of those VGA monitors for a nice, small CRT TV and you'll be in retro heaven 😃 I love my 14" Sony Trinitron for that!
Great follow-up with the temperature! Another way to test that would be to sneak a temperature probe (like those that come with some multimeters) into the screen housing, screw that shut and then retest. That would give you a better measurement of the true internal temperature.
Resistance in parallel keeps the voltage the same, voltage only changes with resistance is in series. But you do draw more current from the signal generator and that can be a problem. But my guess is not,... unpause and see the external screen :)
Only if you’re using an ideal voltage source. In reality, the signal source has some internal resistance (like a battery or capacitor), so the output will drop, depending on the ESR of the source, and the load resistance.
Having HDMI in the loop is going to introduce some lag all on it's own... bearing in mind it's a digital system. Right at the start, I was going to say "an application like this SHOULD be bare-metal and not use Raspian" but it looks like the CGA2HDMI developers and your narration beat me to it. ;) It's VERY nice the LCD display was the big disappointment on this system even when it came out.... this is a superb upgrade. It's funny that we're using a computer far far more powerful than the base system just to handle the display.
I just wanted to say that I love your channel. You've quickly become my favorite retro game/hardware themed channel. Please keep up the wonderful content!
No solo es rapido para bootear, el modo bare metal en la RPi hace que sea posible utilizarla casi como un microcontrolador, apto para sistemas en tiempo real, tales como emulacion de la 1541 o en este caso procesamiento de señal de video
There is a CGA / EGA / YUV / RGB To VGA converter board called "gbs 8200", that's made for Arcades to be able to use new monitors on old hardware, so I assume the response times must be as good or maybe even better than the Raspberry.
Yes, I covered that one in the first part of the LCD replacement video series. It had some issues (size and stability), which can all be worked around, but I'm liking the RGB to HDMI solution better. If you're going to go the route of the GBS 8200, look into GBS Control, which apparently improves it quite a bit.
Dang, I want one, but SMD soldering scares me half to death! I know Aaron from Retro Hack Shack has been wanting to make some to sell, but the CPLD chip required has been in short supply due to the chip shortage.
Yeah, that's a bummer! The chip shortage has definitely been hitting a lot of projects lately. If you haven't done SMD soldering, this is probably not the best project to start. I had trouble with it (as you saw before) and I'm getting a fair bit of experience with SMD already.
@@natethefighter At least in my experience (I was the same and didn't really want to start doing SMD stuff) it is actually fine once you give it a go. You can get little practice boards on eBay with random components of various sizes to mess around with. By the time you've done that a bit you'll probably be fine. Now I really like it; projects like this don't have the really really tiny components and so are fairly forgiving!
I was looking at an article this week with respect to the rsp4020 and that it's click speed off 133 MHz is more than capable of generating a VGA signal. It also has some really neat programmable logic associated with I/o ports that I wonder if it could handle the digital CGA signal with little lag.
When in doubt if a cable will be shielded enough in a fixed installation, wrap the cable in aluminum foil and just attach the foil to a known ground point.
5:55 I can't use flat HDMI cable to my monitors because when i switch the light off in my bathroom (fluorescent lamps) there will be some kind of interference and it will blank my screen for a few seconds. I get the same behavior on several different computers and monitors. After changing the cable to a round cable i haven't got any black screen.
Nice follow up Noel. Just on the screen emulation, I was wondering if selecting Monochrome/Green from the RGB2HDMI menu as well as Invert colours would give a closer emulation of the original green LCD ? Just something occurred to me while watching that segment and I didn't spot anyone else comment on it. I'm expecting my RGB2HDMI board for my A500 today. Looking forward to getting some flicker free interlace modes on my TV 👍
Welcome aboard! Yes, David was really nice and donated a copy of the game for this project (which started all the way back in #DOScember a few months ago).
12:01 does your camera have a global shutter? you may have only 4 frames delay as I thought it partially drew on the LCD. The LCD was lower than the CRT with rolling shutter it could have been missed, shoot the video at 90 degrees next time :) Also (not watched whole video yet) did the pi offer the CGA ntsc interference colours?
Interference: Keep watching 😃 I don't know about the global shutter actually. Good point about doing it at 90 degree angle. But in any case, we're limited at 50 Hz rendering so much more accuracy wouldn't help that much.
I really like that idea! The part I don't like is punching holes on the case, and I don't want to remove the CGA connector either. Hmm... I'll have to think about that. Thanks!
@@NoelsRetroLab as you're soldering a cable directly to the motherboard then going to a soldered header point on the RGBtoHDMI, why don't you cut out the middleman and remove the intermediate DE-9 connector and go straight to header pins/dupont connectors? (I know you didn't have any in the first video but it would be trivial to update)
nice video has always,, a little question for you have you checked if that cga card support plantronics mode ? i know someone said that some cga card support plantronics mode you can check using plantet X3 that support that mode.
hi Noel quite right the project after-all was to replace the screen however you could use a model a pi which has a quad core processor if you really needed to run emulators it is a smaller form factor than th pi b but larger than the pi zero i like the project
Thanks for reading and listening to peoples comments. I just had a thought about emulating the original look of the Green LCD is Black on Green like the Gameboy. However the LCD does Green on Black. Is there a way to possibly invert the colours either with a simple hardware or software hack? Or maybe there's an option for it in the menu? That would be cool.
There's actually an option to inverse colors in the menu. That might be closer to the original, but still not quite the same since the original was on/off and with extra dithering to tell colors apart.
Now I really wonder whether the RPi is maxed out just doing the video... but since it's used bare-bones, it won't be trivial to measure "CPU utilisation".
No artifact composite color from CGA would have been available for PAL countries, the artifact color is reliant on NTSC decoding. There was at least one Amstrad PC with CGA which did offer composite video out, and can produce direct color (cyan, magenta etc.) with PAL modulation.
Right. I think that CGA composite was even less common in PAL countries too since it served almost no purpose. Although it would have been interesting if someone had implemented the color generation like the Apple II PAL (explicitly creating those colors).
12:43: Given that that seems to be an Amstrad-specific non-IBM CGA ROM font, could you try and compare if ICON: Quest for the Ring looks any different on that Amstrad CGA from how it looks on a 100% IBM-compatible CGA?
excellent job Noel!... covered just about all our questions!.. FYI.. got my 464 board working (atleast an image on screen through the RGB to VGA board).. but seems the ram is bad (gray screen, or corrupt pixels).. thanks to your vids i know that i need to replace some ram! (just dunno which ones so gonna do the lot!...if i can find the chips!) do you know of any mod to replace the original ram chips with a single (or 2) SRAM chips? i have 2x 32Kx8 SRAM chips id be interested using...
Hi Noel. Would one of these be any good for converting an Amstrad CPC video out to HDMI? My current setup introduces a LOT of delay in bothe video and audio ( at least 200ms).
I think so! I'm planning on doing a video about it at some point, but it should be much faster than that. You'll also need the analog board that goes with the RGB to HDMI digital board though.
Thank you, i'm going to add the RGBtoHDMI to my PPC512 too! but before, i've to repair the Hard drive board.. i desoldered the roms in trying to add the universal xt bios, and now it stopped working. P.S.: why you left your ROS in spanish? you can simply change links to have firmware in English or in French (you know, it doesn't exist a "spanish" ROS, all three PPC roms are multi-languages. My compliments and respect!
It's actually in my list of things to change the BIOS and the MSDOS version to English ones, but I've been trying to wrap up the screen part (because it also makes it much more pleasant to demo with this screen). But yes, it will happen soon 😃 Good luck with your PPC512!
18:58: There has to be a switching IC that can switch the pins from either a given HDMI source A or a given HDMI source B to a HDMI output C, based on a single pin being low or high. Does anyone know the precise terminology? Some kind of selector or multiplexer? Looking at the HDMI pinout, it seems switching just 16 pins would be enough (leaving HDMI pin 14 N.C. and ground & +5 volts V_CC always connected). Is there a 7400-series IC for that? If yes, then you could add another RasPi to and switch the screen between old and original HW and new. PS: I have found the 74157, which is a quad-input 2-to-1 mux. Four of those may suffice.
The ones that are block diagrams? I either make them directly in Premiere (if they're really simple) or I'll make them in Illustrator and animate transitions in Premiere (mostly animated crops).
Can someone confirm that the correct PCB to use is the one under Kicad_6Bit/v4/? Then, what analog extension to use? I mainly want to be able to display CPC, ZX81 and TI99/4A... Thanks for your help.
Can you believe the awful colours they used for CGA? How many engineers knew it was awful during development, and couldn't do anything about it? It's amazing it ended up being manufactured like that.
Is it?? I actually have no idea about licensing issues of that. I thought it was a standard like USB. In any case, it's generated natively by the Raspberry Pi, so if anything, they probably already dealt with that.
Screw the bloody licences. Lawyers can piss off. Just get on and built it. Job done. The only new parts that have HDMI are the Pi, cable and LCD, which will already have had their licence fee(s) paid. The rest is the original computer, which is old so not a new product.
Yes, you may be right. Although this being bare metal, it would have to be all woven into the same program as opposed to just having multiple processes running on the default OS, which would probably make it harder to pull off.
The pi zero is single core ... you could use a beefier pi (2, 3 or 4) which have 4 cores for other tasks. I have worked on a bare metal project with hoglet and we've talked about using other cores. The time sharing would probably increase lag but not by too much
I got the computer in Spain so it's what's available here. I'm planning on changing the BIOS and MSDOS version to English in the future though (just leave the KEYB setting for the Spanish keyboard layout).
I haven't checked yet, but I was told it was a matter of just changing some links on the board and that was it! And the ROMs are preserved at least in the MAME project I think, so it's definitely doable. Should be interesting to find out anyway.
why are you using a CPLD and a Raspberry Pi you can use an FPGA to do all the work i am not an expert so i would appreciate if someone ware to explain edit : and it will be CGA to LVDS it can be HDMI but removing a layer is better
Just because of the convenience of a project that's already tested and working. I still want to investigate the possibility to reprogram the LCD driver and use that directly (although you'd then lose all the niceties of the RGB to HDMI set up, so it's not all better).
I have no love for the look of the original screen.... the upgrade to the color LCD is perfect. Making old tech better is not necessarily a bad thing. It looks great. It's a wonderful solution. Good Job!
Totally agree. Thanks!
@@NoelsRetroLab Agreed, me too, great job! But it is still fun to see what it looks like side by side and to have that option.
The original LCD was kinda green background with black pattern.
Yours is black background with green pattern.
At 14:24 underneath "Output Color" there is an "Invert"-option.
Maybe this flips the color like it should be.
That might make it closer, you're right. But the original LCD was MDA with CGA emulation. So it actually was using dithering patterns to simulate different CGA colors (look at the pink of the Prince's skin on CGA, that becomes a dithered pattern on the original). So there's more to it, that's what makes me think it's not a matter of just using a different palette.
The biggest problem I had with the LCD was the lack of backlight. Changing the colour pallette file to make it more the light green on dark green might make it more authentic, while still having the advantage of a backlight. Although the advantage of having colour far outweighs any authenticity argument in my book! If I ever find my PPC I am strongly considering this mod, as it will make a great serial terminal for my retro computer projects!
Fans: "Can you emulate the hardware of the Amstrad PPC?"
Noell: "SO, YOU HAVE CHOSEN DEATH."
Great video as always Noel! That's a very nice PC at the 10:23 mark 😉
I really should get back on to my Amstrad PC1512 video project, the RGBtoHDMI would make what I'm trying to achieve so much easier. I really appreciate this very thorough investigation, I think it's answered all of my questions (and a few I didn't realise I had!)
I also thought that computer looked very familiar. Hope Noel is paying some royalties on that 😄
@@TheRetroChannel Haha, it was all agreed in advance, Noel is a gentleman. No need for a copyright strike this time 😉
It is indeed a VERY nice PC. At some point I'd love to have enough space to get a classic one like that. Life goals 😃
Glad the video helped. I keep saying it, but RGB to HDMI is really impressive, and I think it's a fantastic fit for CGA video. I don't remember who first pointed it out to me, but it was someone on Discord. At first I almost dismissed it because "it had a Raspberry Pi" and I don't like overkill, but it's proven to be awesome!
I thought I recognised that bum...
-Dx
HA! I thought that setup looked familiar!
Oh THANK YOU, you fixed the screen. It was tilted slightly in the first video.
I may have seen it before somewhere but seeing it in action, I learned from this video of yours such a thing as those super flat ribbon HDMI cables actually exists.
Thanks for sharing those informations, it's one interesting project to follow.
Glad it was helpful! Cheers.
If you would rather not see the rainbow pattern generated by the Pi on start-up, that can actually be disabled. You'd need to add "disable_splash=1" to config.txt which can be found in the SD card's root directory. The screen will simply remain black until the RGBtoHDMI kicks on.
The screen mode info displayed on boot by the RGBtoHDMI software had been a bit of a pet peeve of mine, so thanks to your video I now know that that function can be disabled. I use this solution on an Amiga 500 which worked out of the box so never actually checked the menu options to see if it could be done... *d'oh*... Powerup Message disabled now as well here.
Turning off the rainbow splash and info overlay has made this a completely seamless and fully integrated solution.
Love your channel, keep them comming :)
Ooh, I didn't know that! I'll definitely do it. So that's great, I learned that trick from you and you learned the power up message. Between the two of us: Perfect silent booting. Yes! 😃👍
Very informative video as usual, thank you!
My pleasure!
Great job. The lag is well within reason for me. Nowhere what I used to deal with when I played online games with a bad internet connection.
Yes, seriously! I played a lot of Quake with 250ms lag! Then I would go into campus and play from the machines there with 10ms lag and people would call me an LPB 😃
Great video Noel! But don't forget to make a second version at some point in the future to cover a possible video upgrade to VGA, as some users and me have proposed you in the past. ;-)
Thank you. And yes, absolutely. I have a lot of plans for it. First is an ISA bus extender, and then the VGA upgrade.
@@NoelsRetroLab I will look forward anxiously for this video! :-D
Don't forget to add sound to complete your computer. Perhaps with some type of internal speakers? ;-)
The original LCD would have a lot of streaking which to me was always off putting, where the extra lag of the new LCD will not put me off at all
Absolutely. The streaking/ghosting of the original LCD was downright insane! When the Prince was moving, you could hardly see a blur on the screen!! 😃
Love the end result, Noel! Great work as always.
Thank you! Cheers!
The new HDMi cable is perfect. BTW, that is not laggy. My Speccy's plugged into the composit in on a freeview box, then into my TV through HDMI. It's 1/2 a second from keyboard click to the screen displaying what you pressed. Playing games on it is fun. LOL.
Ouch! That IS really laggy! Yeah, here I can't complain at all for having an extra frame of delay. I can't even tell while I'm using it.
Between typing out reports for school and some gaming I spent countless hours on that original LCD, trust me you don't want to emulate that...
Haha, yes, I know. It would be fun for about 10 seconds and then just switch away to normal mode 😃
@@NoelsRetroLab True, true.
I don't know why anyone would want to use that. Then again I don't get why people want CRTs. Even when I was a kid I was like these things suck I hope we come up with something better soon. I saw a video by mattKC repairing a gameboy with a wierd pattern in the LCD among other problems (the switch was bad) He actually tried to fix the screen. I'm like WHY!?!?!? Just get a modern gameboy replacement screen kit. The hard parts are already solved all you have to do is swap it out and plug in a ribbon cable. Then you get a nice backlight. Some of them even have a way of getting color out of GB Color enhanced games. I have no idea how that works, but it's a thing. lol I'm far more interested in the actual machines than the accessories such as monitors and disk drives. I honestly don't ever want to use magnetic media ever again. lol
Great video Noel. some great questions asked there.
Glad it was helpful!!
It looks great with that LCD
Me encantan tus videos Noel. ¿Has visto las reparaciones de GadgetUK de Amigas 1200?. Me encantaría ver algo así en tu canal como sabes. Ánimo.
I am very interested in this. These days in retro community, whenever someone comes up with a good design, it becomes a commercial product to sell. It really feels like a big breath of fresh air to see such a good idea as an open source project! I will be building a Superfo Harlequin 128 v4A in near future, and it outputs RGB. I don't have a monitor that has an RGB input, the only screen I have that would work with the Harlequin is the house TV with its SCART input Unfortunately my better half doesn't like my toys around the house, out of the man cave. I have a lot of old VGA monitors, and I use one of them with a ZX-VGA-Joy on my 48K Spectrum. I believe this device does not output VGA, but as far as I know HDMI to VGA conversion is quite good with the cheap Chinese converters. I am torn between buying another ZX-VGA-Joy, or building this and using it with a HDMI-VGA converter. I really prefer to use my old monitors with my retro computers because of the 4:3 aspect ratio, I could get a new HDMI capable monitor, but they are all wide screen and I hate that look.
Yes, it's nice to see it not being commercialized to death like a lot of projects in a certain retro computer... If you have a lot of VGA monitors, maybe one of them accepts 15KHz signals and you can feed it the Spectrum one directly (once you combine intensity). Alternatively, swap out one of those VGA monitors for a nice, small CRT TV and you'll be in retro heaven 😃 I love my 14" Sony Trinitron for that!
What a great project, and you covered it very comprehensively.
Nice work, sir!
Great follow-up with the temperature! Another way to test that would be to sneak a temperature probe (like those that come with some multimeters) into the screen housing, screw that shut and then retest. That would give you a better measurement of the true internal temperature.
Love the shirt! ❤️
Resistance in parallel keeps the voltage the same, voltage only changes with resistance is in series. But you do draw more current from the signal generator and that can be a problem. But my guess is not,... unpause and see the external screen :)
Only if you’re using an ideal voltage source. In reality, the signal source has some internal resistance (like a battery or capacitor), so the output will drop, depending on the ESR of the source, and the load resistance.
Having HDMI in the loop is going to introduce some lag all on it's own... bearing in mind it's a digital system.
Right at the start, I was going to say "an application like this SHOULD be bare-metal and not use Raspian" but it looks like the CGA2HDMI developers and your narration beat me to it. ;)
It's VERY nice the LCD display was the big disappointment on this system even when it came out.... this is a superb upgrade.
It's funny that we're using a computer far far more powerful than the base system just to handle the display.
Good job, as always!
Thank you! Cheers!
You never fail to amaze me. Thumb up
Great, informative video Noel.
Thanks! 👍
I just wanted to say that I love your channel. You've quickly become my favorite retro game/hardware themed channel. Please keep up the wonderful content!
Thank you so much! I'm really glad you're enjoying it!
That MSDOS shirt hits me right in the childhood.
Great video. This is an interesting topic.
Thanks. Glad you think so!
No solo es rapido para bootear, el modo bare metal en la RPi hace que sea posible utilizarla casi como un microcontrolador, apto para sistemas en tiempo real, tales como emulacion de la 1541 o en este caso procesamiento de señal de video
There is a CGA / EGA / YUV / RGB To VGA converter board called "gbs 8200", that's made for Arcades to be able to use new monitors on old hardware, so I assume the response times must be as good or maybe even better than the Raspberry.
Yes, I covered that one in the first part of the LCD replacement video series. It had some issues (size and stability), which can all be worked around, but I'm liking the RGB to HDMI solution better. If you're going to go the route of the GBS 8200, look into GBS Control, which apparently improves it quite a bit.
Dang, I want one, but SMD soldering scares me half to death! I know Aaron from Retro Hack Shack has been wanting to make some to sell, but the CPLD chip required has been in short supply due to the chip shortage.
Yeah, that's a bummer! The chip shortage has definitely been hitting a lot of projects lately. If you haven't done SMD soldering, this is probably not the best project to start. I had trouble with it (as you saw before) and I'm getting a fair bit of experience with SMD already.
@@NoelsRetroLab I think I just gotta find a non-threatening starter project for SMD to get my feet wet!
@@NoelsRetroLab Chip shortage? You mean the let's make a new excuse to raise prices shortage.
@@natethefighter At least in my experience (I was the same and didn't really want to start doing SMD stuff) it is actually fine once you give it a go. You can get little practice boards on eBay with random components of various sizes to mess around with. By the time you've done that a bit you'll probably be fine. Now I really like it; projects like this don't have the really really tiny components and so are fairly forgiving!
You got it backwards. SMD soldering is super easy and thru hole is hard. Solder mask is almost magical.
I was looking at an article this week with respect to the rsp4020 and that it's click speed off 133 MHz is more than capable of generating a VGA signal. It also has some really neat programmable logic associated with I/o ports that I wonder if it could handle the digital CGA signal with little lag.
When in doubt if a cable will be shielded enough in a fixed installation, wrap the cable in aluminum foil and just attach the foil to a known ground point.
Ah, great tip! I didn't think of it, but it makes sense.
5:55 I can't use flat HDMI cable to my monitors because when i switch the light off in my bathroom (fluorescent lamps) there will be some kind of interference and it will blank my screen for a few seconds. I get the same behavior on several different computers and monitors. After changing the cable to a round cable i haven't got any black screen.
Oh wow! I wonder if there's something wrong about that cable or it's the lack of shielding.
Your fluoresent light probably uses an inductive ballast and when you switch it on/off, there might be a voltage spike on the mains.
Time to switch to LED bulbs...
I just love this channel ❤️
Nice follow up Noel. Just on the screen emulation, I was wondering if selecting Monochrome/Green from the RGB2HDMI menu as well as Invert colours would give a closer emulation of the original green LCD ? Just something occurred to me while watching that segment and I didn't spot anyone else comment on it. I'm expecting my RGB2HDMI board for my A500 today. Looking forward to getting some flicker free interlace modes on my TV 👍
Just subscribed!
I watch 8-bit guy and I saw you used PlanetX3 (at least, I saw the floppy) as one of the test games! Kudos for that!
Welcome aboard! Yes, David was really nice and donated a copy of the game for this project (which started all the way back in #DOScember a few months ago).
12:01 does your camera have a global shutter? you may have only 4 frames delay as I thought it partially drew on the LCD. The LCD was lower than the CRT with rolling shutter it could have been missed, shoot the video at 90 degrees next time :) Also (not watched whole video yet) did the pi offer the CGA ntsc interference colours?
Interference: Keep watching 😃 I don't know about the global shutter actually. Good point about doing it at 90 degree angle. But in any case, we're limited at 50 Hz rendering so much more accuracy wouldn't help that much.
One suggestion for upgrade: external HDMI (some handy place for unplug internal monitor or even HDMI splitter).
I really like that idea! The part I don't like is punching holes on the case, and I don't want to remove the CGA connector either. Hmm... I'll have to think about that. Thanks!
@@NoelsRetroLab as you're soldering a cable directly to the motherboard then going to a soldered header point on the RGBtoHDMI, why don't you cut out the middleman and remove the intermediate DE-9 connector and go straight to header pins/dupont connectors? (I know you didn't have any in the first video but it would be trivial to update)
LMAO those SMD caps really bothered me with the first one. This is much better. Not that I could have done any better myself. LOL
Add a serial modem connection to the pi so it's a mainframe you access ^^
Haha, I like that one! 😃👍
nice video has always,, a little question for you have you checked if that cga card support plantronics mode ? i know someone said that some cga card support plantronics mode you can check using plantet X3 that support that mode.
Well, shoot, I don't know! 😃 I'll have to try later and find out.
hi Noel quite right the project after-all was to replace the screen however you could use a model a pi which has a quad core processor if you really needed to run emulators it is a smaller form factor than th pi b but larger than the pi zero i like the project
Thanks for reading and listening to peoples comments. I just had a thought about emulating the original look of the Green LCD is Black on Green like the Gameboy. However the LCD does Green on Black. Is there a way to possibly invert the colours either with a simple hardware or software hack? Or maybe there's an option for it in the menu? That would be cool.
There's actually an option to inverse colors in the menu. That might be closer to the original, but still not quite the same since the original was on/off and with extra dithering to tell colors apart.
@@NoelsRetroLab definitely include video that if you can. Compare it side by side to original. See what it looks like! :)
Another interesting Video. However can you please move the screen to the left by a mm or so as the border alignment is killing my OCD. Lol
Haha, actually that one is centered. It's just that the camera was at a slight angle from the left, so it looks like it's not quite centered 😃
@@NoelsRetroLab hmmm, lol
Now I really wonder whether the RPi is maxed out just doing the video... but since it's used bare-bones, it won't be trivial to measure "CPU utilisation".
Yeah, not sure. That was just a guess thinking about what the RPI needs to be doing, but maybe there are cycles to spare.
afaik cpu is just reading gpio in a loop and stuffing it into the gpu framebuffer, at lest inside the raster lines its 100% utilization
did you test some 16 colors games ? or the recent infamous demo 16colors ? the amstrad pc1512 has special versions patchs of some Sierra games..
No artifact composite color from CGA would have been available for PAL countries, the artifact color is reliant on NTSC decoding. There was at least one Amstrad PC with CGA which did offer composite video out, and can produce direct color (cyan, magenta etc.) with PAL modulation.
Right. I think that CGA composite was even less common in PAL countries too since it served almost no purpose. Although it would have been interesting if someone had implemented the color generation like the Apple II PAL (explicitly creating those colors).
12:43: Given that that seems to be an Amstrad-specific non-IBM CGA ROM font, could you try and compare if ICON: Quest for the Ring looks any different on that Amstrad CGA from how it looks on a 100% IBM-compatible CGA?
excellent job Noel!... covered just about all our questions!..
FYI.. got my 464 board working (atleast an image on screen through the RGB to VGA board).. but seems the ram is bad (gray screen, or corrupt pixels).. thanks to your vids i know that i need to replace some ram! (just dunno which ones so gonna do the lot!...if i can find the chips!)
do you know of any mod to replace the original ram chips with a single (or 2) SRAM chips? i have 2x 32Kx8 SRAM chips id be interested using...
Thanks! I don't know of any board to do use a SRAM substitute, but it should totally be doable. It could be a fun little project to do that actually.
oh and i meant to add is there room and power for an ssd drive? that might be a cool storage solution
Hi Noel. Would one of these be any good for converting an Amstrad CPC video out to HDMI? My current setup introduces a LOT of delay in bothe video and audio ( at least 200ms).
I think so! I'm planning on doing a video about it at some point, but it should be much faster than that. You'll also need the analog board that goes with the RGB to HDMI digital board though.
Wasn't Prince of Persia designed with Composite output in mind ?
Thank you, i'm going to add the RGBtoHDMI to my PPC512 too! but before, i've to repair the Hard drive board.. i desoldered the roms in trying to add the universal xt bios, and now it stopped working. P.S.: why you left your ROS in spanish? you can simply change links to have firmware in English or in French (you know, it doesn't exist a "spanish" ROS, all three PPC roms are multi-languages. My compliments and respect!
It's actually in my list of things to change the BIOS and the MSDOS version to English ones, but I've been trying to wrap up the screen part (because it also makes it much more pleasant to demo with this screen). But yes, it will happen soon 😃 Good luck with your PPC512!
18:58: There has to be a switching IC that can switch the pins from either a given HDMI source A or a given HDMI source B to a HDMI output C, based on a single pin being low or high. Does anyone know the precise terminology? Some kind of selector or multiplexer? Looking at the HDMI pinout, it seems switching just 16 pins would be enough (leaving HDMI pin 14 N.C. and ground & +5 volts V_CC always connected). Is there a 7400-series IC for that? If yes, then you could add another RasPi to and switch the screen between old and original HW and new. PS: I have found the 74157, which is a quad-input 2-to-1 mux. Four of those may suffice.
So it seems that getting into the BIOS is not an issue. The Pi boots up well before any post screen comes up.
Yes, exactly. Way faster than the PPC.
Can you also show Windows 1.00 running on that machine with a mouse?
Yes, that would be fun! And I need to try GEM as well.
Small question, Noel -how do you create those explainer animations? Which software?
The ones that are block diagrams? I either make them directly in Premiere (if they're really simple) or I'll make them in Illustrator and animate transitions in Premiere (mostly animated crops).
What is the make, model and tech. spec. of the LCD panel please
What about Plantronics 16 color(colour) mode?
👍 🍀
This music 😁 i searching it please tell me.from where IT is i have this song on cracked worms 😅 intro
Can someone confirm that the correct PCB to use is the one under Kicad_6Bit/v4/?
Then, what analog extension to use? I mainly want to be able to display CPC, ZX81 and TI99/4A...
Thanks for your help.
That's correct. For the analog I think you want the Kicad_analog_6bit one.
@@NoelsRetroLab Ok, thanks!
What are the _Extender_ files for?
I have tried to go the other direction to have a VGA source display on a CGA or EGA monitor and it is not as straight forward as it seems
Right. Very different refresh rates. I think you need to do some serious signal conversion.
Whose CGA to SCART adapter are you using and where can I get one?
That was the CGA to SCART from Serdashop: www.serdashop.com/CGA2SCART-PRO
What about hdmi to cga?
DOOD!
Can you believe the awful colours they used for CGA? How many engineers knew it was awful during development, and couldn't do anything about it? It's amazing it ended up being manufactured like that.
It was the 80s so I guess that didn't mind because that palette of those loud colours were prominent in 80s pop culture.
⭐⭐⭐⭐⭐
I hate to go there, but isn't HDMI licensing a problem here?
Is it?? I actually have no idea about licensing issues of that. I thought it was a standard like USB. In any case, it's generated natively by the Raspberry Pi, so if anything, they probably already dealt with that.
@@NoelsRetroLab The way the lawyers see it, only the pi itself has had its license fee paid. A new product has to pay it again. Yeah, I hate it.
Crazy!! I had no idea. Hopefully this is considered an add-on, so it's all clear.
Screw the bloody licences. Lawyers can piss off. Just get on and built it. Job done. The only new parts that have HDMI are the Pi, cable and LCD, which will already have had their licence fee(s) paid. The rest is the original computer, which is old so not a new product.
my comment here
pi zero has plenty horse power to do extra tasks
Yes, you may be right. Although this being bare metal, it would have to be all woven into the same program as opposed to just having multiple processes running on the default OS, which would probably make it harder to pull off.
The pi zero is single core ... you could use a beefier pi (2, 3 or 4) which have 4 cores for other tasks. I have worked on a bare metal project with hoglet and we've talked about using other cores. The time sharing would probably increase lag but not by too much
Why ms dos is in spanish?
because it's a Spanish computer with localized dos.
I got the computer in Spain so it's what's available here. I'm planning on changing the BIOS and MSDOS version to English in the future though (just leave the KEYB setting for the Spanish keyboard layout).
@@NoelsRetroLab Challenging, wish someone dump the BIOS and upload to archive.org or somewhere.
I haven't checked yet, but I was told it was a matter of just changing some links on the board and that was it! And the ROMs are preserved at least in the MAME project I think, so it's definitely doable. Should be interesting to find out anyway.
Nicee
Me: such a mess
He: Ezzzzz
why are you using a CPLD and a Raspberry Pi you can use an FPGA to do all the work i am not an expert so i would appreciate if someone ware to explain
edit : and it will be CGA to LVDS it can be HDMI but removing a layer is better
Just because of the convenience of a project that's already tested and working. I still want to investigate the possibility to reprogram the LCD driver and use that directly (although you'd then lose all the niceties of the RGB to HDMI set up, so it's not all better).
@@NoelsRetroLab reprogramming the LCD driver is a good choice too
best of luck and thanks for the video