Re: [gentoo-user] Re: [OT] Re: Re: Grub2 and is the upgrade a tooth puller.

[Peter Humphrey]

On Saturday 30 June 2012 15:52:13 Grant Edwards wrote:
> On 2012-06-30, Peter Humphrey <peter@××××××××××××××.org> wrote:
> > The displays were graphic stroke writers, as used in submarines and
> > other warships - none of that nasty raster technology. I think the
> > display drivers were more complex than the CPUs - all that D-A
> > conversion of multiple values at once. Can you imagine X and Y
> > amplifiers to drive a spot in a circle - and meet up?
>
> That's actually pretty trivial: Feed a sine wave into X and cosine
> into Y.  AC amplitude controls size, DC offsets control position.
> Hint: cosine is just sine phase shifted by 90 degrees, so you can do
> that with a single resistor and capacitor.

Hmm. Hadn't thought of doing it that way. Neat.

> > Then a display full of them.
>
> Been there, done that. :)

:-)

-- 
Rgds
Peter