30 Jan
2013
30 Jan
'13
4:38 p.m.
On Jan 30, 2013, at 2:30 PM, Chris Elmquist <chrise at pobox.com> wrote:
On Wednesday (01/30/2013 at 11:28AM -0500), David
Riley wrote:
Having a user-programmable FPGA means you can do whatever you
want (as long as you can program an FPGA, which has been a
somewhat contentious topic around here). I'd certainly be
looking to at least support pixel doubling as well as the
type of interpolation one usually sees on LCD computer
monitors as a stock feature; I know at least I'd prefer
doubling over interpolation, but lots of people have an
aversion to "jaggies". Then again, I grew up playing lots of
pixel-doubled games when I was growing up.
What a lot of the nicer console emulators support as far as
upconversion is a simplified attempt to mimc the blooming
On Jan 30, 2013, at 9:34 AM, Chris Elmquist
<chrise at pobox.com> wrote:
Definitely one of my "one of these days" projects, though I'd much
rather use an FPGA than a CPU to handle the video. I'm tired of
how awful composite video looks on my LCD TV because of their
crappy decoding (my Bt878 TV cards from the early 2000s do a much
better job) and the latency looks awful. Expanding it out to more
analog formats would be handy to a lot of folks, I guess. What
kind of price would be palatable to people? I doubt I could get
it down below $70 in any kind of realistic quantity.
oh... excellent. I'd pay $150 for such a thing as long as it converts
to a standard that will be around for a while-- such as DVI/HDMI.
It would be fine if it puts a letter box around the legacy image too--
all the way around-- and doesn't up convert so that one pixel from the
legacy turns into say, five on the modern display. I'm not a big fan
of blooming the image. I'm after as crisp of a image on the new display
as we had with the original tube when it was operating correctly. from the original CRT (which, for games meant to be
played
on cheap color TVs of the '80s, was kind of important). I'd
like to be able to do something like that, too.
The only thing I was brainstorming about when a CPU is
involved is that
you could also fork the video into something like VNC protocol and send
it over a network for remote display.
Given the option, I'd like to put USB and Firewire on it as
well, which would generally need a CPU to at least set up a
framebuffer. Any reasonable design would require a CPU for
housekeeping purposes, at least; no reason it can't be
directing traffic out to USB/Firewire/Ethernet as well.
So far, between the FPGA, a small microcontroller, HDMI
encoder and a semi-beefy quad ADC (video people: 12 bits
at max 65 MHz ought to be enough for a lot of applications,
right?), an audio ADC and associated buffering, the parts
come to about $110 in quantity 10. That doesn't factor in
the PCB (which won't be cheap at those quantities) or the
assembly (most of which could be done by hand), but it
gives a reasonable picture. It also doesn't factor in the
connectors, but those generally aren't expensive.
I've a lot on my plate, though. I'd need more spare
cycles before I handle this, and I still want to get more
done on my swiss-army-knife QBUS board before I commit to
any more projects. But if anyone wants to help with
either of those...
- Dave