Use ST High via screencast, without mono monitor

[Kirkman]

I do not have a monochrome monitor. But there is some mono software I would like to test.

Today I thought: what if I turn off my monitor, so the ST doesn't know what sort of monitor is attached, and then run it remotely via the CosmosEx screencast function?

Alas, the "ST High" option remained grayed out.

My question: Would it be possible to modify the screencast to allow it to work with ST High, even if you don't have a monochrome monitor?

What is the actual trigger that allows the option to become available? Does the monochrome monitor send out a special signal to the ST when it is connected?

[AdamK]

You need hardware trigger. You need to connect two signals in ST monitor output. 1st is GND, 2nd is MONO DETECT.

[Kirkman]

Can I just run a little wire between the two pins on the monitor port? Or does it require more than that?

[Kirkman]

The answer to my own question is, YES, you can just run a wire connecting pins 4 (MONO DETECT) and 13 (GND) of the monitor port.

After doing that, if you have CE_CAST.PRG in your Auto folder, the Atari will boot into mono and you can control it via the Cosmos Ex screencast.

I wrote up a little blog post about what I did in case anyone wants to see.

[dhedberg]

Hehe, that's an interesting way to achieve mono out. You could buy a VGA adapter and connect the ST to a modern flat screen as well. It will give you mono and low/medium resolutions if the monitor can deal with those frequencies..

[wongck]

At the time when I was using my STFM with a colour monitor, to test Hi-rez software, I used the software called Sebra
https://www.atariuptodate.de/en/5600/sebra
No extra hardware needed.
But of course using Screencast is kind of a cool method.

[Kirkman]

Hehe, that's an interesting way to achieve mono out. You could buy a VGA adapter and connect the ST to a modern flat screen as well. It will give you mono and low/medium resolutions if the monitor can deal with those frequencies..

Fair point! But I was trying to avoid buying and keeping a second monitor, and wanted to see if the CosmosEx could serve for this purpose. And it did!

[Kirkman]

At the time when I was using my STFM with a colour monitor, to test Hi-rez software, I used the software called Sebra
https://www.atariuptodate.de/en/5600/sebra
No extra hardware needed.
But of course using Screencast is kind of a cool method.

Wow, I hadn't heard of Sebra before. I'll have to to check it out.

[Moulinaie]

At the time when I was using my STFM with a colour monitor, to test Hi-rez software, I used the software called Sebra
https://www.atariuptodate.de/en/5600/sebra
No extra hardware needed.
But of course using Screencast is kind of a cool method.

Wow, I hadn't heard of Sebra before. I'll have to to check it out.

I used SEBRA in the 80's when the monochrom monitor was to expensive to me.
If I remember well, you can see the 200 upper lines, the 200 lower lines or the 400 lines using some grey levels to display the 640x400 into 640x200.

A really good piece of software.

Guillaume.