Sidequest: VGA scan doubler

[exxos]

Happy to help. I don't think many realise how important these types of video mods are yet even. With RF basically dead and scart pretty much gone, HDMI is the only way forward to keep the ST's connected to a modern screen. I'm sure once the ball starts rolling people will be flooding to towards the things!

[Smonson]

I've just sent off the boards order for prototype version 2 of this mod, so keep your fingers crossed for me! 8-)

scandoubler2.png

[exxos]

I've just sent off the boards order for prototype version 2 of this mod, so keep your fingers crossed for me! 8-)

:bravo: :coolpics:

[Icky]

:thumbup: - nice board. Looking forward to seeing it working.

[troed]

I'm sure once the ball starts rolling people will be flooding to towards the things!

Yeah ... about one board, at least, per every active ST user today. It's a game changer.

/Troed

[beel1]

Out of curiosity are there enough free IOs on the V2 to handle a 4th bit per channel? (for STEs, even if I know that instead of piggybacking the Shifter, that would require to solder everything from the mainboard) :D
I think that needs 12 more IOs I guess?

Anyway that's a really nice work :bravo:

[Smonson]

Thanks beel1.

Out of curiosity are there enough free IOs on the V2 to handle a 4th bit per channel? (for STEs, even if I know that instead of piggybacking the Shifter, that would require to solder everything from the mainboard) :D

Probably, but I didn't wire it up that way. The RAMs are 16 bits wide, so I guess that means (3 colours * 2 RAMs) plus the IO in from the shifter and out to VGA = 12 extra IOs. Can always go up from the TQFP100 to the 144 version of the chip if necessary - I reckon it could fit :)

[Smonson]

I put the first of these new boards together today, and got a good result out of it:

sc2-3.jpg

sc2-1.png

(excuse the moire effect, it's just the effect this TV has on my phone camera)

sc2-2.png

There's a bit of analogue noise in the picture, but I suspect that is probably a combination of my bargain-basement VGA cable, dodgy hand-made ungrounded IDC pin header adapter, and the fact that this is a cheap TV and not a monitor. I also haven't done a proper video "porch" - it's just dropping to to the normal black point around the horizontal sync, which is good enough for the purposes of a prototype.

These pics are at 50Hz, haven't made it work for 60Hz yet. Still - it's promising. The picture is nice and steady. I'm content with it!

[exxos]

Nice one! :cheers:

[JezC]

Looks like some great progress on this!
:thumbup: :goodpost: :bravo: