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Author Topic: The ultimate VGA to SCART adapter  (Read 33819 times)

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gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #40 on: August 28, 2020, 11:00:11 am »
I'm still a bit overwhelmed by MPLAB X IDE though, but i think all i need to do is import the .hex file, then build the project, using the programmer as the device. The target IC being a PIC16F18313 should already be set up, yes?

Sorry, I'm quite unskilled. Probably you can use MPLAB X IDE to write the PIC without having to build the project, but I don't know how. If you are going to rebuild the project then you don't need the .hex file. Just select the target IC, add the source .c code and, just in case, press "Clean and Build Project". Then, to write each PIC press "Make and Program Device".

Also, i was half planning to use this for the MiSTer. Do you know if the H-sync input for the PIC16F18313 will pass composite sync through? Does it depend on what the v-sync port is doing as well?

Sorry, I have no idea. Does the MiSTer have have a composite sync output? If so, why do you need the adapter?  Can't you connect it directly to the composite sync input of the SCART?

Also, great avatar! I have to steal that picture :)

I'm happy to see you liked it, althought it would probably loose a battle with Usagi  ;)

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #41 on: August 30, 2020, 07:39:42 am »
Probably you can use MPLAB X IDE to write the PIC without having to build the project, but I don't know how. If you are going to rebuild the project then you don't need the .hex file. Just select the target IC, add the source .c code and, just in case, press "Clean and Build Project". Then, to write each PIC press "Make and Program Device".

Expect to hear from me in a month when the PICKIT 3.5 arrives and i can't figure it out, lol :) You updated the source.c file to switch resolutions in 740 lines?

Quote
Does the MiSTer have have a composite sync output? If so, why do you need the adapter?  Can't you connect it directly to the composite sync input of the SCART?
https://github.com/MiSTer-devel/Main_MiSTer/wiki/Direct-Video
The MiSTer has a setting called direct_video which takes the native video output of the FPGA cores and pumps it out the VGA port on the I/O board, if you have one, and also out the inbuilt HDMI port. It also has an option to turn on composite sync, yes. And with almost any cheap HDMI-to-VGA converter you get 240p RGBS. But the MiSTer will pump composite sync at any res, i think. And not all cores output natively in 240p (some microcomputers, Apple, 486, etc are all higher.)

It would be nice if your adapter would work with composite sync under that environment, i guess. You could also just turn off composite sync and use normal 240p RGBHV however.

Quote
I'm happy to see you liked it, althought it would probably loose a battle with Usagi  ;)
To Usagi as he used to be. Nowdays everyone whips his butt, lol :)
« Last Edit: August 30, 2020, 07:41:32 am by buttersoft »

gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #42 on: August 30, 2020, 01:01:54 pm »
Expect to hear from me in a month when the PICKIT 3.5 arrives and i can't figure it out, lol :) You updated the source.c file to switch resolutions in 740 lines?

You mean the countdown_duration parameter? Yes, it has been updated.

The MiSTer has a setting called direct_video which takes the native video output of the FPGA cores and pumps it out the VGA port on the I/O board, if you have one, and also out the inbuilt HDMI port. It also has an option to turn on composite sync, yes. And with almost any cheap HDMI-to-VGA converter you get 240p RGBS. But the MiSTer will pump composite sync at any res, i think. And not all cores output natively in 240p (some microcomputers, Apple, 486, etc are all higher.)

It would be nice if your adapter would work with composite sync under that environment, i guess. You could also just turn off composite sync and use normal 240p RGBHV however.

I'm a bit confused. The adapter generates the composite sync requiered by the TV from Hsync and Vsync. If the MiSTer can generate the composite sync, it does not need this adapter.

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #43 on: August 30, 2020, 07:52:35 pm »
It would be for protection from signals over 15kHz, in this case. Not a massive gain, i was merely curious as to whether it could handle composite sync.

gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #44 on: August 31, 2020, 09:59:14 am »
It would be for protection from signals over 15kHz, in this case. Not a massive gain, i was merely curious as to whether it could handle composite sync.

I'm sorry it can not handle it. Anyway, maybe the overfrequency protection is useless in this case. I don't know anything about TV internals. Can it be damaged if the frequency is too high?

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #45 on: August 31, 2020, 10:29:53 pm »
I don't think any TV or PVM from about 1990 onwards would be damaged, they way they capture sync means they'll just fail to sync to anything outside their range. But i'm sure it's best to be safe. Some old Arcade monitors and older computer monitors certainly will be damaged, as they're circuitry was only meant to see 15kHz, and they will still work to capture whatever signal is input and damage themselves. They may not fail instantly, but in some cases the damage can be cumulative.

Those wouldn't have SCART sockets of course, but i'm not using SCART and I'm building a couple of your adapters :) I was just trying to find out what they can handle and what uses they might be put to.
« Last Edit: September 01, 2020, 08:06:06 pm by buttersoft »

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Re: The ultimate VGA to SCART adapter
« Reply #46 on: September 11, 2020, 11:42:06 am »
I am happy to say I have found two stores selling implementations of this adapter.

One is https://www.arcadexpress.com/es/arcadevga/457-cable-arcade-vga-scart-usb-5v-12v-con-audio.html
This implementation looks almost identical to the original, except the position of the LEDs.

Another one is http://vga-scart-converter-f-15.mozello.es/catalog/params/category/0/item/1443803/
The appearance of the latter is quite different. The switches are more accessible so that the power supply or the aspect ratio of the screen can be changed without having to open the adapter. Another notable difference is that it has a female VGA input and two SCART outputs, one male and one female. The adapter can be connected directly to the TV with the male SCART connector. Alternatively, it can be connected via the female connector using a SCART cable.
« Last Edit: September 12, 2020, 12:42:20 pm by gambaman »

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #47 on: October 22, 2020, 06:35:41 am »
Hi gambaman, just wanted to say I got the pickit 3 and a few pics have have been giving this vs a whirl! It all works very nicely.  I did modify your original design,  I have one version that has RGBS and the LEDs and it fits into a db15hd backshell - same as a regular db9 backshell. It uses an soic version of the pic chip.

I thought it might be nice to make some 15khz detector dongles, sort of thing. But it's not too hard to add a cable or cables in there as well.

I'll upload the modded design in a couple of days when I get back from holidays :)
« Last Edit: October 22, 2020, 06:37:33 am by buttersoft »

gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #48 on: October 27, 2020, 01:06:53 pm »
Hi gambaman, just wanted to say I got the pickit 3 and a few pics have have been giving this vs a whirl! It all works very nicely.  I did modify your original design,  I have one version that has RGBS and the LEDs and it fits into a db15hd backshell - same as a regular db9 backshell. It uses an soic version of the pic chip.

I thought it might be nice to make some 15khz detector dongles, sort of thing. But it's not too hard to add a cable or cables in there as well.

I'll upload the modded design in a couple of days when I get back from holidays :)

I'm happy to hear that. Please, upload photos.

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #49 on: October 27, 2020, 09:09:11 pm »
Please let me know if the project doesn't share properly, i haven't had to do this before!
https://easyeda.com/account/project/detail?project=b3a7e09672ef4b80a204782462e99254

can be ordered cheapest from OshPark, but you can also download the gerbers from there and upload to another fab:
https://oshpark.com/shared_projects/tDs1Slud

I built the only SOIC PIC i have right now into one adapter, but the 3d models of the boards look like this:


It solders directly to the back of a DB15HD male solder plug, and should fit inside any backshell, with room to connect a cable too.
« Last Edit: October 28, 2020, 12:27:26 am by buttersoft »

haynor666

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Re: The ultimate VGA to SCART adapter
« Reply #50 on: February 05, 2021, 09:37:22 am »
I am happy to say I have found two stores selling implementations of this adapter.

One is https://www.arcadexpress.com/es/arcadevga/457-cable-arcade-vga-scart-usb-5v-12v-con-audio.html
This implementation looks almost identical to the original, except the position of the LEDs.

Another one is http://vga-scart-converter-f-15.mozello.es/catalog/params/category/0/item/1443803/
The appearance of the latter is quite different. The switches are more accessible so that the power supply or the aspect ratio of the screen can be changed without having to open the adapter. Another notable difference is that it has a female VGA input and two SCART outputs, one male and one female. The adapter can be connected directly to the TV with the male SCART connector. Alternatively, it can be connected via the female connector using a SCART cable.

I bought two VGA F-15 some time ago (thanks for help with this gambaman) and so far works very nice. Price is also very good.
One thing I noticed - sometimes device fails to switch back TV signal after resolution change. I have to quit game and start again just to force resolution change. It does happen rarely so not a problem for me. Putting device directly in TV scart is also quite handy - no need for scart cable. This is very comfortable for me because I have TV very close to PC.
« Last Edit: February 05, 2021, 09:39:48 am by haynor666 »

gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #51 on: February 08, 2021, 05:57:30 am »
One thing I noticed - sometimes device fails to switch back TV signal after resolution change. I have to quit game and start again just to force resolution change. It does happen rarely so not a problem for me.

Hi. Do you mean that sometimes resolution dosen't change when switching games? Does it happen with any emulator?

gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #52 on: February 08, 2021, 11:55:47 am »
MonochromeVGA is a project from Aitor Gómez to enjoy the charm of those monochrome monitors of the time in VGA displays. It makes it possible to select green, amber or B&W as monochromatic color, among others, as well as to change color to monochrome or vice versa easily. You may ask why I'm posting about it here. The reason is that Aitor has combined the MonochromeVGA with my project to get the MonochromeRGB:



MonochromeRGB allows several possible configurations of use:

-VGA to [optionally monochrome] VGA, without the need for any power supplyA
-SCART to [optionally monochrome] SCART, also without the need for any power supply
-VGA at 15.7Khz horizontal frequency to [optionally monochrome] SCART with selectable 4:3 <-> 16:9 aspect change for compatible TVs, being necessary 5V power supply via microUSB or from the VGA connector itself

I would like to collaborate with Aitor to develop a dual output version for TATE games. Stay tuned.
« Last Edit: February 08, 2021, 06:31:56 pm by gambaman »

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Re: The ultimate VGA to SCART adapter
« Reply #53 on: February 09, 2021, 05:22:10 pm »
One thing I noticed - sometimes device fails to switch back TV signal after resolution change. I have to quit game and start again just to force resolution change. It does happen rarely so not a problem for me.

Hi. Do you mean that sometimes resolution dosen't change when switching games? Does it happen with any emulator?

Sometimes after starting game I get black screen - TV displays OSD info and looks like TV is not getting any signal. Today I've tested many games but it didn't happen even single time.

gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #54 on: February 10, 2021, 06:42:14 am »
One thing I noticed - sometimes device fails to switch back TV signal after resolution change. I have to quit game and start again just to force resolution change. It does happen rarely so not a problem for me.

Hi. Do you mean that sometimes resolution dosen't change when switching games? Does it happen with any emulator?

Sometimes after starting game I get black screen - TV displays OSD info and looks like TV is not getting any signal. Today I've tested many games but it didn't happen even single time.

Strange. I don't know the reason. I'm sorry I can't help you.  :-[

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #55 on: February 15, 2021, 08:01:38 pm »
So that mod for passthrough dongle i was working on is done. This one is a double-ended version, male HD15 to female HD15. It has the LED's, taking in H-sync and V-sync and allowing C-sync through only when it detects 15kHz, blocking everything else. It allows you to plug in any VGA or VGA-toBNC or -SCART cable to the out end as required.

Points to note:
-You will need to wire the RGB lines from input to output yourself.
-You will need to wire up all the input/output pins on the PCB including all ground lines (just in case)
-You will need to fab the board at 0.8mm thick.
-You will need to either use a PCB HD15 male plug or trim a solder HD15 male plug. (https://www.aliexpress.com/item/1005001418455591.html?spm=a2g0s.9042311.0.0.1f164c4dN9vaBg)
-You will need to 3D-print the housing for yourself :)
-Make sure you have the means to program the PIC before doing anything else like ordering parts!

More general info is in this thread :)

PCB - https://oshpark.com/shared_projects/mMqybOjf
housing - https://anonfiles.com/vbg3f5J7p0/DB9_double_mine_-_complete_tiny_v5_stl PM for updated link, pls!





« Last Edit: August 10, 2022, 04:09:19 am by buttersoft »

Gunstar

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Re: The ultimate VGA to SCART adapter
« Reply #56 on: February 19, 2021, 09:36:32 am »
@buttersoft - Does your redesign use Zener and Schottky diodes?

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #57 on: February 24, 2021, 05:55:24 pm »
No it does not. My version is cut down from the original, and uses no diodes. Were you thinking i should add some to this reduced design?

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Re: The ultimate VGA to SCART adapter
« Reply #58 on: November 29, 2021, 02:48:06 pm »
UPDATE: They do not sell the box version anymore, buy all the design files are available here.

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Re: The ultimate VGA to SCART adapter
« Reply #59 on: February 21, 2022, 04:19:37 pm »
It's really sad they are not making it anymore. I would really sink my teeth in 2 of them F15s
http://vga-scart-converter-f-15.mozello.es/catalog/params/category/0/item/1443803/

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Re: The ultimate VGA to SCART adapter
« Reply #60 on: February 23, 2022, 09:49:19 am »
It's really sad they are not making it anymore. I would really sink my teeth in 2 of them F15s
http://vga-scart-converter-f-15.mozello.es/catalog/params/category/0/item/1443803/

The MonochromeRGB converter is more expensive, but you can buy it here: https://hackaday.io/project/176201-monochromergb

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Re: The ultimate VGA to SCART adapter
« Reply #61 on: August 08, 2022, 04:45:17 am »
I bought one of the premade cables from Arcadexpress earlier on in the year, and I'm trying to understand if it's faulty or not.

I've been getting video interference with most TVs I've tried it with. I've also had audio interference.

I thought it might be a ground loop problem, but I've discovered that *just having the cable plugged in* creates audio noise on the TVs SCART input. Other SCART cables connected to the same input do not do this. Nothing is connected at the other end of the cable.

Handling the VGA end increases the noise, especially with a 3.5mm cable connected. Other SCART cables I *have* to touch the audio pins to induce noise, which I'd expect.

Is the cable faulty or is this something to be expected in the design?

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Re: The ultimate VGA to SCART adapter
« Reply #62 on: August 08, 2022, 05:36:50 am »
Cools, are the video/audio grounds connected to the shield ground? That would explain the noise while handling VGA end.

If the cable has poor shielding that can create similar issues too.

Probably a good idea to check what is connected to ground with a DMM. May as well check for resistance on the audio and video lines while you are there too.

Because the video and audio grounds are usually shared at both the TV and PC ends, you may simply find that running audio out to some desktop speakers works better than through the TV. A ground loop isolator may also help. But it sounds like you have video interference as well.

Before you could buy them from shops and aliexpress, I used to make similar cables by hand at my kitchen bench for forum members, and a few extra hobby dollars, after the kids had gone to sleep. 1-2 hours for a cable. Was a fun "gig" economy thing to do that helped other retrogamers.

I still make my own cables and they are still the best (of course! :P ), but can't really compete with the Arcadexpress prices vs my time and effort.

FWIW, I usually left out the audio from my VGA/SCART cables - if you really want to, for most TVs you can simply run a cheap cable (3.5mm male to red/white RCA male) and it is done anyway.

Check out my completed projects!


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Re: The ultimate VGA to SCART adapter
« Reply #63 on: August 09, 2022, 12:08:20 pm »
Thanks Zebidee. I took a meter to it, and discovered the SCART plug wasn't grounded properly. Opening it up, the metal shield wasn't connected to pin 21, I guess it had jiggled out in transit. Slotting that pin back into place solved the crazy bad interference I was getting.

While open, I spotted none of the R G B grounds were connected either, and the chosen cable didn't have enough conductors to support them. Checked the VGA end and they were empty on the PCB too.

The original design says some connections are optional, but since I was still seeing and hearing interference, I figured I should just replace the whole SCART cable part wirh a fully wired one and see what happens.

4 hours and some sorely tested patience later, I've done that, along with belt-and-braces joining all the video grounds. The video noise was still present, albeit reduced further. Audio noise, no difference.

I've done a bunch more messing around, not sure if its video card or mains socket but fingers crossed I've eliminated all video noise. Audio is there but the level is pretty low - low enough at  normal volume for it not to be audible anyway. Might try your suggestion although I would need to inject the audio into the SCART plug as none of my TVs have a separate input - should I just make sure audio and video grounds are separated in the cable and see if that makes a difference?

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Re: The ultimate VGA to SCART adapter
« Reply #64 on: August 09, 2022, 09:31:18 pm »
Thanks Zebidee. I took a meter to it, and discovered the SCART plug wasn't grounded properly. Opening it up, the metal shield wasn't connected to pin 21, I guess it had jiggled out in transit. Slotting that pin back into place solved the crazy bad interference I was getting.

While open, I spotted none of the R G B grounds were connected either, and the chosen cable didn't have enough conductors to support them. Checked the VGA end and they were empty on the PCB too.

The original design says some connections are optional, but since I was still seeing and hearing interference, I figured I should just replace the whole SCART cable part wirh a fully wired one and see what happens.

That is good news!  :)

You only need one ground from the VGA - it depends on your cable, but typically it will be connected to pin 10 or 5.

Pins 6,7,8 are often not used, but usually connected/soldered to ground at the video card and TV ends anyway.

For making a VGA-SCART video cable, you need just six wires from VGA. RGB (1,2,3) + syncH&V (13,14) + GND (5,6,7,8,10). Just twist all the available VGA grounds (video+sync, not shield) together and run them into one of the SCART RGB ground pins.

Make sure you don't have any other random wires from VGA connected to SCART ground, here I'm talking mostly about the monitor ID/data pins (VGA 11,12,15) or the 5v pin (VGA 9). The wires can be any colour, so don't assume, check with DMM.

You'll also need to link the syncs together for SCART. Exactly how, and what your cable does with sync, is another issue we can get to later.

Quote
4 hours and some sorely tested patience later, I've done that, along with belt-and-braces joining all the video grounds. The video noise was still present, albeit reduced further. Audio noise, no difference.

I've done a bunch more messing around, not sure if its video card or mains socket but fingers crossed I've eliminated all video noise. Audio is there but the level is pretty low - low enough at  normal volume for it not to be audible anyway. Might try your suggestion although I would need to inject the audio into the SCART plug as none of my TVs have a separate input - should I just make sure audio and video grounds are separated in the cable and see if that makes a difference?


Separating the video/audio grounding points may make a notable difference. Even with all the grounds connected back at TV/PC, the electrons still seek the shortest path of least resistance. If you can give the audio a ground return that is a little more direct, it will take it, and interfere less with your video ground return.

Video and audio signals operate at very different frequency levels (Mhz vs Khz) and there is usually some frequency filtering, so providing better ground returns may help.

Having said this, you will probably still get some interference, a kind of variable hum, sometimes sounds like a Jedi light sabre, with running the game audio output through the TV. In my experience, the hum varies mostly with screen brightness, a strong indication of voltage regulation issues. There are some very powerful voltages going around in TVs, and their voltage regulation and noise filtering can only do so much.

This is why, whenever I use a TV for a cab, I usually prefer a separate audio amplifier with its own power supply. Effectively, this separates the video and audio systems. The TV speakers can be re-used for $zero if you want, or get some new ones (speaker are where prices can be whatever you are willing to pay). There are some some decent & inexpensive audio board amps available with a range of features, choose according to your taste (prices vary with features, but around $5 to $30, check your marketplace). This also makes it easier to control things like volume, bass/treble etc.

In my current Aussie lowboy build I'm using a ZX-502MT (cost <$10) like this (clicking on pic will take you to the thread discussion):





Finally, installing a ground loop isolator for the audio inputs may help. There are many simple board-type audio isolators available under $10, so worth a try. They come with a range of different input/output options for attaching audio cables, from RCA connectors to screw terminals to 3.5mm and combos. Search your favourite online marketplace. For example:

Audio ground loop isolator



« Last Edit: August 09, 2022, 09:35:01 pm by Zebidee »
Check out my completed projects!


gambaman

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Re: The ultimate VGA to SCART adapter
« Reply #65 on: March 10, 2023, 10:15:54 am »
Hello. Is it possible to buy the dongle assembled? A friend of mine is interested.

So that mod for passthrough dongle i was working on is done. This one is a double-ended version, male HD15 to female HD15. It has the LED's, taking in H-sync and V-sync and allowing C-sync through only when it detects 15kHz, blocking everything else. It allows you to plug in any VGA or VGA-toBNC or -SCART cable to the out end as required.

Points to note:
-You will need to wire the RGB lines from input to output yourself.
-You will need to wire up all the input/output pins on the PCB including all ground lines (just in case)
-You will need to fab the board at 0.8mm thick.
-You will need to either use a PCB HD15 male plug or trim a solder HD15 male plug. (https://www.aliexpress.com/item/1005001418455591.html?spm=a2g0s.9042311.0.0.1f164c4dN9vaBg)
-You will need to 3D-print the housing for yourself :)
-Make sure you have the means to program the PIC before doing anything else like ordering parts!

More general info is in this thread :)

PCB - https://oshpark.com/shared_projects/mMqybOjf
housing - https://anonfiles.com/vbg3f5J7p0/DB9_double_mine_-_complete_tiny_v5_stl PM for updated link, pls!





buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #66 on: March 10, 2023, 05:24:20 pm »
Well, for the record, i don't build them to sell as there wouldn't be any profit in it. I did make one or two spares though, so PM me and we can work something out :)

EDIT: Gambaman, did you PM me?
« Last Edit: March 18, 2023, 08:35:51 pm by buttersoft »

Rion

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Re: The ultimate VGA to SCART adapter
« Reply #67 on: March 25, 2023, 08:32:42 am »


gambaman (SCART VADER)
I see that you back in 07/28/2020 improved the resolution switching.
Is there any way to improve it even further?
Seeing as some games in Retroarch are struggling when switching from 240p to 480i.
« Last Edit: March 25, 2023, 08:38:15 am by Rion »

Rion

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Re: The ultimate VGA to SCART adapter
« Reply #68 on: March 28, 2023, 05:57:05 pm »
Well, for the record, i don't build them to sell as there wouldn't be any profit in it. I did make one or two spares though, so PM me and we can work something out :)

EDIT: Gambaman, did you PM me?

PM sent

JP24

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Re: The ultimate VGA to SCART adapter
« Reply #69 on: April 17, 2023, 03:49:15 pm »
So that mod for passthrough dongle i was working on is done. This one is a double-ended version, male HD15 to female HD15. It has the LED's, taking in H-sync and V-sync and allowing C-sync through only when it detects 15kHz, blocking everything else. It allows you to plug in any VGA or VGA-toBNC or -SCART cable to the out end as required.

Points to note:
-You will need to wire the RGB lines from input to output yourself.
-You will need to wire up all the input/output pins on the PCB including all ground lines (just in case)
-You will need to fab the board at 0.8mm thick.
-You will need to either use a PCB HD15 male plug or trim a solder HD15 male plug. (https://www.aliexpress.com/item/1005001418455591.html?spm=a2g0s.9042311.0.0.1f164c4dN9vaBg)
-You will need to 3D-print the housing for yourself :)
-Make sure you have the means to program the PIC before doing anything else like ordering parts!

More general info is in this thread :)

PCB - https://oshpark.com/shared_projects/mMqybOjf
housing - https://anonfiles.com/vbg3f5J7p0/DB9_double_mine_-_complete_tiny_v5_stl PM for updated link, pls!

I'm very interested in building this!  Do you have a components list to complete this project? I think I have them all figured out (pretty green in this realm) just not sure on the 10n cap--is it utilizing this one?... https://es.rs-online.com/web/p/condensadores-ceramicos-multicapa/5373369

Also I'm too new to this forum, so can't PM for your updated model link.

Thanks!

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #70 on: April 17, 2023, 07:19:40 pm »
I have uploaded the model here - https://anonfiles.com/W3EaXel0z2/DB9_double_complete_tiny_v5_stl

The caps and the resistors are all 1206 SMD packages. The caps are 10nF and 100nF - and are optional, though recommended, i think. (The cap you linked to was not SMD/surface-mount and was 2.2nF)

Make SURE you have a device that can program the PIC first, like a PicKit 3 or something.


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Re: The ultimate VGA to SCART adapter
« Reply #71 on: May 28, 2023, 03:27:36 pm »


gambaman (SCART VADER)
I see that you back in 07/28/2020 improved the resolution switching.
Is there any way to improve it even further?
Seeing as some games in Retroarch are struggling when switching from 240p to 480i.

Sorry, I have just read your post. Not sure what you mean. A resolution switch should just deactivate the output for a pair of frames.

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #72 on: June 06, 2023, 08:15:05 pm »
I have decided to make a small batch of the passthrough protection dongles for sale. I'll put up a separate post with more info shortly.

Gambaman, i'd love to talk to you about compiling your code for myself - my last attempt at this went pear-shaped and it'd be nice to figure out what I'm doing wrong :)

EDIT: righto, my sale thread was moved to the correct place by Scott :)

http://forum.arcadecontrols.com/index.php/topic,167729.0.html
« Last Edit: June 07, 2023, 07:13:32 am by buttersoft »

Rion

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Re: The ultimate VGA to SCART adapter
« Reply #73 on: August 04, 2023, 01:31:35 am »
I have uploaded the model here - https://anonfiles.com/W3EaXel0z2/DB9_double_complete_tiny_v5_stl

The caps and the resistors are all 1206 SMD packages. The caps are 10nF and 100nF - and are optional, though recommended, i think. (The cap you linked to was not SMD/surface-mount and was 2.2nF)

Make SURE you have a device that can program the PIC first, like a PicKit 3 or something.

The link is no longer working.
But would you be willing to add your dongle to Hackaday with instructions?  :notworthy:

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #74 on: August 05, 2023, 09:21:25 pm »
The link is no longer working.
But would you be willing to add your dongle to Hackaday with instructions?  :notworthy:

I have split the body and the lid, and added a version of the lid that has holes so you don't have to drill. You may still need to chase them with a drillbit.

https://anonfiles.com/v0b5K46dz6/DB9_double_mine_lid_v3_with_holes_stl
https://anonfiles.com/udbfKa6ez0/DB9_double_mine_lid_v2_no_holes_stl
https://anonfiles.com/wfb8K46cz3/DB9_double_mine_body_v2_stl

And no, sorry, i am not keen to write up more details instructions - too busy with the kids. Everything you need is in this thread, and the little PCB is stencilled with part values. Passive SMDs are all 1206 sized, though 0805 will fit.  I might be able to answer specific questions, if you need.

I will say again though, make sure you have the means to program the PIC before anything else :)

ajshell1

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Re: The ultimate VGA to SCART adapter
« Reply #75 on: August 21, 2023, 10:10:18 am »
I hate to bother you after you've already reuploaded it, but anonfiles has shut down.

So yeah. I'm afraid that you'll have to reupload again.

buttersoft

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Re: The ultimate VGA to SCART adapter
« Reply #76 on: August 22, 2023, 02:18:53 am »
Happy to upload again, don't know why i never shared it here :)

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Re: The ultimate VGA to SCART adapter
« Reply #77 on: May 19, 2024, 10:56:36 am »
I am happy to see they are selling another variant here: