Atari ST Display Basics

All information relating to connecting your ST to a modern TV/monitor.
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Bikerbob
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Re: Atari ST Display Basics

Post by Bikerbob »

So when using the monitor output to the SC1224 it could be pal or ntsc does not matter correct?

What controls the saturation of colour on the ST. IF I have one that puts good colour to the monitor, but another computer same monitor, and the colour is not so good.. red is high, not as bright.. (only changed the computer, no settings on monitor)

Any help on that?

Thanks :)

James
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Re: Atari ST Display Basics

Post by exxos »

The shifter in the ST is driven from the 5v from the PSU. Also the caps around the RF box causes issues, its why I sell recap kits for PSU & video.
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Bikerbob
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Re: Atari ST Display Basics

Post by Bikerbob »

Ok, i was planning on getting a PSU kit from you, I will ask you about the video when the time comes.

James
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Re: Atari ST Display Basics

Post by phlod »

Question to the Atari pros in here: Is the Falcon's ST Low and Medium somehow different from the same resolutions on the ST(e)? What I mean is, does the Falcon hooked to a VGA monitor and switched to ST Low not output 15.75kHz? I'm trying to figure out if my ST to VGA cable is the issue here, or if I missed where the Falcon does these differently.

I currently have 2 NEC monitors, a 19" I know works with both the Falcon and my STe, and a 17" which works and looks crisp in ST Low, Medium, and High on the Falcon, but only works in a heavily jailbar'd High Res on my STe. I know this cable isn't great, because even on the 19" monitor the picture doesn't look the best on the STe. At least, it looks nowhere near as nice as on my Falcon in the same resolutions.

Falcon is more-or-less stock Just a 14MB upgrade. STe has 4MB but no acceleration. Should I try ordering another cable? What do you guys think?
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Re: Atari ST Display Basics

Post by krupkaj »

French Atari 7800 console is similar. Its videochip MARIA outputs S-video signal (like GTIA in 8bit Atari or VIC in C64), but the French version of console has RGB output. And what is interesting, it use the same DIN 13 like Atari ST, even the pinout and SCART cable is the same. Inside the console is small board with RGB decoder instead of TV modulator.
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Re: Atari ST Display Basics

Post by troed »

IngoQ wrote: Thu Aug 24, 2017 2:15 pm [*] GND on ST, 12V on STE
I don't think it's this easy. It's GND on 520ST (I have one here), but surely Ube's switches work on a lot of STs and not just STE and it requires 12V

edit: So now I'm more confused than before. I just looked at the 520ST schematics and they clearly show pin 8 connected to 12V (trough a 1.2kOhm resistor) for both non-modulator and modulator revisions.
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Re: Atari ST Display Basics

Post by Icky »

Nice post IngoQ and interesting discussion of the variants out there. Its always good for us to preserve this information for the future.

I found looking at the pinout reminded me of an article I submitted in one of the Atari ST User magazines when I was 21 I think (a long time ago). It got me trying to remember how I wrote the article on the ST and on what software, as the magazine wanted the article in a specific format.

http://www.atarimania.com/mags/hi_res/a ... -63_98.jpg
http://www.atarimania.com/mags/hi_res/a ... -63_99.jpg

I think it may of been Neochrome for the images and 1st Word Plus for the writeup.
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exxos
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Re: Atari ST Display Basics

Post by exxos »

troed wrote: Sun Mar 18, 2018 10:23 am
IngoQ wrote: Thu Aug 24, 2017 2:15 pm [*] GND on ST, 12V on STE
I don't think it's this easy. It's GND on 520ST (I have one here), but surely Ube's switches work on a lot of STs and not just STE and it requires 12V

edit: So now I'm more confused than before. I just looked at the 520ST schematics and they clearly show pin 8 connected to 12V (trough a 1.2kOhm resistor) for both non-modulator and modulator revisions.
I just checked pin 8 on STE & STM is via 1.2K resistor. Assuming a typo Ingo ?
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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Re: Atari ST Display Basics

Post by exxos »

I think I see the problem.. on info-coach it says the same as Ingo wrote.. but later down the page it says "12V pullup" , so the info on the site is actually wrong at the top of the page..
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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Re: Atari ST Display Basics

Post by troed »

exxos wrote: Sun Mar 18, 2018 1:02 pm I just checked pin 8 on STE & STM is via 1.2K resistor. Assuming a typo Ingo ?
It's "common knowledge" that there are somce machines that don't put out 12V ... but considering even the 520ST schematics has it I'm quite confused as to exactly which those machines would be.
12V / 10mA pin (STE) : On STE this pin is connected to 12V.
GND pin (ST) : On 520STF this pin is connected to GND
http://info-coach.fr/atari/hardware/int ... _connector

edit: Yeah you saw it as well. Actually I recall the info on that page was recently changed due to a discussion on A-F. Before that it excluded more models from 12V IIRC.

(I've started to doubt what my 520STM does. I'm currently running it on 5V only waiting for a picoPSU to arrive, so it obviously cannot put out 12V .. )
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