[Open-graphics] Re: DDC injection box Re: Boot-time video mode

[James Richard Tyrer]

Rene Herman wrote:
> James Richard Tyrer wrote:
> 
> [ Haven't followed along and am missing context ]
> 
>> TV interlaced (NTSC 640x480 or PAL <what ever it is>)
>> TV progressive  (NTSC 640x480 or PAL <what ever it is>)
> 
> The DVD standard is 720x480 (720x576 for PAL). Getting that format 
> unscaled out onto a connected TV is important I guess.

Actually, you can display 640x480 (square pixels) on NTSC.  But you are 
correct that an actual digital TV signal that has the pixel clock a 
multiple of the color sub-carrier is 720x480 (pixels are NOT square).

So, PAL with square pixels would be 768x576.

>> 50 or 60 Hz also selects if TV is NTSC or PAL.
> 
> Possible, but note that many DVD players on the European market play 
> NTSC DVDs fine and turn them into PAL-60, meaning many TVs available 
> here nowadays also do PAL-60. At least all flat-panel TVs I've seen upto 
> now do.

That would only matter if using the TV output.  Perhaps we will also 
need a switch to select the TV output format.  If it is the component 
video output the NTSC should display OK on a TV that supports PAL-60.

> Yes, they of course also do 50, but PAL-60 is not an unimportant format 
> then. Again, playing NTSC-DVD format video on the connected TV is why 
> you'd like to be able to just do PAL-60 if your TV supports it.

IAC, this is only to select the default boot video mode.  Well actually, 
PAL-60 would probably be better for that than 50 Hz PAL.

-- 
JRT