Good device to plug the amiga to an LCD?

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Hi
Any connection between an Amiga and a SCART socket will require a 270 to 470 ohm resistor on the CSYNC signal. If you use the CSYNC signal with any other adaptor you will also need the resistor. It's purpose is to reduce the amplitude from 4.8V to 1V or less that all modern TVs or adaptors require on a composite video input.

Ian
 
Stedy said:
Hi
Any connection between an Amiga and a SCART socket will require a 270 to 470 ohm resistor on the CSYNC signal. If you use the CSYNC signal with any other adaptor you will also need the resistor. It's purpose is to reduce the amplitude from 4.8V to 1V or less that all modern TVs or adaptors require on a composite video input.

Ian
Click to expand...

Thanks for the clarification :)

:thumbsup:

diskers said:
I use a DSUB23 to SCART with 3 resistors and it's fine. If I find some time I will try the new Ian tweak with the other 3 capacitors. I think that I have somewhere my original Amiga cable. I will try it with the converter (if I can find it :D).
Click to expand...

Cool as mate :)

.aZtOcKdOg | .Key-J FReeLY
 
OK Folks,
I've tested an old original Amiga SCART cable with the SCART/HDMI device and it's a no go.... (flashing white and black). :roll:




PS. About the DSUB23 to DSUB15 (VGA), I don't really see any utility to use one. First it will only allows you tu use a VGA cable but you still have to have the other end as a SCART. This adapter is fine for a Multisync monitor or for use with GBS - with HSYNC and VSYNC. You will add yourself more work - You will have to carefully check the connection routes from DSUB23 to DSUB15 then connect them to the SCART and add at least 3 resistors. PAL and NTSC Amiga had both DSUB23 connectors right? So I don't think it's impossible to find a cable with this connector in US maybe even cheaper than the connectors that I have. You will only take it for the connector and make all wiring and resistors to SCART.

OK: http://www.ebay.com/itm/Commodore-A...pt=UK_VintageComputing_RL&hash=item3a640480bb

This one isn't so pretty, rather ugly - it have a DSUB25 shell - but according the the schematics it will work with the converter (I have made exactly the same cable and use it with the converter) and it's cheaper: http://www.ebay.com/itm/AMIGA-RGB-V...pt=UK_VintageComputing_RL&hash=item19dc19e06e
 
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Been told that it has different firmware, but since I don't have both, I can't tell if that's right

Btw. I wonder if you can use that cable, that is usually taken to connect an amiga to a 1084S.
 
Is this reliable as source?

http://www.idiots.org.uk/vga_rgb_scart/

I see that there are resistors, thanks for explaining why we need them (it seems that a direct connection without downgrade the voltage on these pin will fry the logic board of the LCD tv, but cause less damage to older TV).

So I've tried what I have: 2 LCD tv and the monitor, with the plain VGA out and is a no go; neither can hook on the 15KHz frequency.

Tried with the vgabox that I use for the Dreamcast and it is a no go too; it is just a pass trough for the VGA, so it is the same as having the vga cable attached directly to the tv.

At this point I would try the approach with the SCART, since I have a spare connector (if the diagram that I've posted is correct; there are various diagrams with slightly different variations), but I am worried about the db23 to vga thou...indeed it is useful only if you have to attach a multisync CRT.

I've seen people cutting the DB25 to make DB23, since it is easier to find DB25 around...feels so homemade thou :P

I will make the cable this weekend, but will take at least a week or more to get the hdmi/SCART box, so for this week I will have to continue to use the composite connection sadly.

Eysenbeiss: I've seen the same exact box going around ebay for quite a while; not sure who makes them, since as johnim said, it is a gbs wrapped in a box, with the connector soldered on it. It may have a different firmware, but I would not bet on that, unless I can see a legit website that gives some sort of reassurance...and even at that point I would just get the firmware and get the plain gbs for less than half the price of that box.

I can't curse enough for the lack of standards all over the world; usb came too late sadly, so here we are, trying to make something that may work in different areas of the world :) Pretty sure that in 30-40 years from now; someone will try to hook a current gen console or computer to their scifi audiovisual system and will blame us in the same way ;)
 
It's reliable for a VGA output pin 1,2,3 as RGB etc and a Radeon Card. With a DSUB23 to DSUB15 as I said before you must check the routes from DSUB23 to DSUB15 in order to not make a mess.
OK, that's what I found for the DB23 to DB15 converter (please note that I don't know it the converter you have is the same). Don't blame me if something goes wrong.

> Amiga DB23 - VGA DB15
> 3 (red) 1 (red)
> 4 (green) 2 (green)
> 5 (blue) 3 (blue)
> 11 (hsync) 13 (hsync)
> 12 (vsync) 14 (vsync)
> 16 (ground) 5 (ground)
> 17 (ground) 6 (ground r)
> 18 (ground) 7 (ground g)
> 19 (ground) 8 (ground b)
> 20 (ground) 10 (ground)
 
Update:

So I went ahead and got the GBS and the SCART one...

Got today the GBS, the scart is coming next week probably (the maker is in CA, but for some reason it takes longer than a shipping from NJ....go figure).

So I tried it and so far no luck.

With the adapter 23-15 from Amikit, if I plug the VGA in, I get no signal (tried to change the input, nothing). Figured out from the documentation, that the VGA in accept only 30.5-32K,which is not what the Amiga output. The alternative is the other input

So I used the cable included; cut a VGA cable and hooked up the wires, as requested (Red, Green, Blue, Ground, Hsync and Vsync) by the board (the colors for the Hsync and Vsync were not the same, so I went ahead and tested each pin with a multimeter, to be sure, comparing them on the VGA pinout). BTW Diskers, your pinout is correct; opened the 23 to 15 adapter and it match.

Now in this way, I get something: when I push the auto button, the card find the signal, but it is unusable, since it flickers and move around (attached a picture to give you an idea).

Do I have to change the settings on the board? Looks like there is some sort of vertical and horizontal refresh setting to do, but the whole thing is in chinese, so I have no clue what is says :)

Did I made a mistake with the connection?

Also another thing which is strange: when I power up the amiga, if the video cable is attached, I get no boot, and the green power led flash slowly, like when you get a guru meditation, but it doesn't reboot...just continue to flash steadily, pulsing slowly.

If I detach the cable, turn it off and on again, it boots fine; after that, I can plug the video cable without problems. No idea why it does that.

NExt weekend I will play with the scart adapter, but for now I just have this. Any suggestion is more than welcome, since you already have the board configured :)

Thanks!
 

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How are you powering the GBS? The image you are getting is due to a power overload supplied to the unit normally.

You can get the correct 2A 5V PSU that will work perfectly with the gbs from eBay for around £2.

Or alternatively wire the power pin from the Amiga port to the other gbs power cable that came with it. Many don't recommend doing that, but it does work. I've used mine that way perfectly ok.

Btw, have you read through the pinning thread about flickerfixers? Loads of discussion about the gbs and how to wire it correctly.

Sent from my Nexus 7 using Tapatalk HD
 
Harrison said:
How are you powering the GBS? The image you are getting is due to a power overload supplied to the unit normally.

You can get the correct 2A 5V PSU that will work perfectly with the gbs from eBay for around £2.

Or alternatively wire the power pin from the Amiga port to the other gbs power cable that came with it. Many don't recommend doing that, but it does work. I've used mine that way perfectly ok.

Btw, have you read through the pinning thread about flickerfixers? Loads of discussion about the gbs and how to wire it correctly.

Sent from my Nexus 7 using Tapatalk HD
Click to expand...


The unit is powered with a 5V 2A AC adaptor, that I use for various other 5V devices (is one of the multi voltage ones; checked the output and it fluctuates between 5.1 and 4.9V).

The video port does not have enough power for the board...it is suggested at least 2A, while the Amiga video port output max 100mA (unless the data sheet that I have is incorrect), I have an ATX adapter, so I can try to get the 5V from the molex for the HD; I have few cables that has the molex connector to get power for the fan; I can use these cables to power the board and the Amiga at the same time.

I've indeed check around, but it seems that there are various pin settings for various use.

If you work with 15KHz, then your only option is a 23 to 5 pin, and plug the cable on the EGA connector (which I can't find anywhere, so I made my own connector, not even stores that sell Jamma cards has that connector). The alternative is the 6 wires VGA cable, included with the board, but from what I understand, that will require a 31KHz signal

More experimenting on the way...I am too tired now to even try anything else now :) Thanks!
 
meduseld said:
With the adapter 23-15 from Amikit, if I plug the VGA in, I get no signal (tried to change the input, nothing). Figured out from the documentation, that the VGA in accept only 30.5-32K,which is not what the Amiga output.
Click to expand...

I wonder why you plug to vga though gbs has rgb input?
 
meduseld said:
Is there any other option that I am missing? I have an LCD with VGA and HDMI, which I would like to use with the amiga.
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Yeah monitors who can do 15Khz with a Commodore RGB-VGA adapter:

-Dell ST2320L
-Dell ST2340L

And I've been told the ST2420 and 40L can do it also.
 
Ivan: because it is easier to grab a VGA cable, and plug it from one side on the amiga adaptor, and the other end on the GBS, but I get no signal. This board has 4 different input, I thought that going for the easiest one was the best choice.

Roy: then there is something wrong at this point with the board? I've got a 25 pin connector, cut it, crimped it with pin 3 for red, 4 for green and 5 for blue; then pin 10 on grey cable (some says to put grey and yellow together, others says that grey is enough), and pin 20 for black (ground); plugged in and now the best that I get is a green screen with some noise on it :(

BuzzFuzz; sadly my monitor is not supporting 15K, so I can't connect it directly via the db23-db15 adaptor :( That's why I bought the GBS and the HDMI/SCART converters; to see which one is able to give me a good output.
 

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hi just the grey is needed

also try connectin to the other grounds


you may need to adjust the settings on the board as I did when I first had both of mine

also look at harrisons flickerfixer thread
 
meduseld said:
Roy: then there is something wrong at this point with the board? I've got a 25 pin connector, cut it, crimped it with pin 3 for red, 4 for green and 5 for blue; then pin 10 on grey cable (some says to put grey and yellow together, others says that grey is enough), and pin 20 for black (ground); plugged in and now the best that I get is a green screen with some noise on it :(.
Click to expand...
grey is enough
 
meduseld said:
The unit is powered with a 5V 2A AC adaptor, that I use for various other 5V devices (is one of the multi voltage ones; checked the output and it fluctuates between 5.1 and 4.9V).

The video port does not have enough power for the board...it is suggested at least 2A, while the Amiga video port output max 100mA (unless the data sheet that I have is incorrect), I have an ATX adapter, so I can try to get the 5V from the molex for the HD; I have few cables that has the molex connector to get power for the fan; I can use these cables to power the board and the Amiga at the same time.
Click to expand...

The GBS spec does state it needs a 5V 2A adapter, but in all my tests this overloads the GBS and creates scrambled screens. These range from seeing the image, but with lots of snow. A green and black rolling screen, and a pink broken up screen. All of these issues were due to over voltage.

Now I know the Amiga video port does only supply a very low mA, but it does actually work and powers the GBS perfectly well using the power cable that came with the GBS.

I've indeed check around, but it seems that there are various pin settings for various use.

If you work with 15KHz, then your only option is a 23 to 5 pin, and plug the cable on the EGA connector (which I can't find anywhere, so I made my own connector, not even stores that sell Jamma cards has that connector). The alternative is the 6 wires VGA cable, included with the board, but from what I understand, that will require a 31KHz signal
Click to expand...

Nope, it is designed for 15Hz. What would be the point in an upscaler if it didn't accept 15Hz inputs to output VGA?

The VGA port on the GBS won't work with the Amiga using a 23pin to VGA adapter because that port isn't for that type of signal. You have to use the supplied cable and make your own cable. Looking at your wiring image remove the yellow wire from your 23pin connector as it won't work with that connected. Everything else is OK, except I also found it didn't work until I joined all 4 of the ground pins together, with any one of the pins connected to the black ground wire. It then works perfectly.
 
I see, so basically they got it wrong even on their manual....I need less power and not 2A? Will try to hook up the power cable that came with it on the video port.

Also do I have to hook up all the other grounds? (16 trough 20); all the posts that I've found here were just mentioning one ground, maybe that could be the reason why it won't work!

Will try today (without the yellow, since it is not needed). Thanks a bunch!
 
meduseld said:
Also do I have to hook up all the other grounds? (16 trough 20); all the posts that I've found here were just mentioning one ground, maybe that could be the reason why it won't work!
Click to expand...

you already have one ground (black) it is enough
 
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