ATARI 1040 STe black RGB good Composite

[exxos]

With me nothing is obvious :lol:

Im using UBE Switch if that helps? What do that mod do anyway?

The UBE allows you to hookup VGA to the ST.. But it will only work with MONO.. unless you have a multisync RGB monitor which supports 15Khz.

https://www.exxosforum.co.uk/forum/viewt ... f=27&t=161

There is a little switch on top to switch between mono and colour modes.

[zChris]

Yeah i got a 15kHz monitor that i've used with other Ataris ST's. Confirmed that the switch, cable, monitor works with another board :)

Unfortunately pressing the switch didn't help.

Worth nothing is that the monitor that's hooked up to RGB doesn't seem to see a signal at all since it goes into sleep mode.

[exxos]

A monitor should not really care about missing RGB.. Monitors only really look for V-sync AFAIK. So you should probably continuity check V&H sync on your socket etc., If you have a scope then see if they are switching. Some monitors are able to use syncs over composite. But not all monitors can AFAIK.

[zChris]

Looking on the monitor port i measured pin 12 (Horizontal) and Pin 9 (Vertical) (ref. https://info-coach.fr/atari/hardware/interfaces.php).

Picture 1 and 2 is Horizontal while picture 3 is vertical. Looks fine to me. :?

HORIZONTAL1.png

HORIZONTAL2.png

VERTICAL1.png

[exxos]

Vertical should be switching down to 0v.. It looks like it's going down to only 4v.. Are you testing this with nothing connected to the monitor port?

[zChris]

Yeah, only thing connected is the composite cable. Can it be that it switches down to 0 too fast for my equipment to measure it ?

[exxos]

Yeah, only thing connected is the composite cable. Can it be that it switches down to 0 too fast for my equipment to measure it ?

Looks like you got the same scope as me anyway...

Unfortunately VSYNC goes right back to the large GSTMCU...

Capture.PNG

Maybe someone else can confirm the output on their own STE... But it looks like your chip is fried to me.

[zChris]

Even though the composite works ?

[exxos]

Even though the composite works ?

Theoretically should not work with that either. #Welcome to electronics :lol:

[zChris]

:S Hope someone can measure the signal on how it should look like so we can make a crosscheck