SE/30: Invert screen pixels?

[sandy_frank]

I would like to invert the screen from black on white to white on black. I recall there being a control panel which could do that, but I think it also only worked as a magnifier?

Anyways: does anyone know if something else exists? I feel like a system init going in and modifying QuickDraw bits might be resource intensive. How about flipping it in a modified ROM? I have a Rominator coming...

Or how about using op amps to flip the video signal driving the CRT?

Why would one want to do this? I slapped a green CRT in one of my 30's and it would look so much cooler inverted.

 

[croissantking]

Would an inverter chip work for this? As you are simply flipping all the 0s<—>1s.

 

[Daxeria]

There's Reverse Screen by Darin Adler, but it was written in 1986 for System 3.x, suffers from cursor flickering under 6.x, and is totally incompatible with 7.x.

 

[ymk]

Would an inverter chip work for this? As you are simply flipping all the 0s<—>1s.

It should. An XOR IC would give you a normal/invert switch input.

 

[Bolle]

No extra hardware needed to accomplish this… the serial output stream of video data runs through one of the PALs, so you can just invert the output polarity in the fusemap and burn a replacement.