On Thu, 14 Apr 2005 16:23:36 -0400, you wrote:
>The emulators always start the emulation with a fresh scanline,
>so you'll always get the same value with this method. And the
Real 2600 hardware will always start a fresh scanline upon bootup as well.
The Atari does not *read* the sync signal from the TV and match its own
WSYNC counter to that. (There's no way for it to do that even if it
wanted to - there's no output from the TV back to the Atari.) The Atari
*generates* the horizontal sync signal, and it's the TV's job to recognize
it and get the picture lined up. Upon bootup, the 2600 just starts
outputting the TV signal from the beginning of a scanline.
Upon bootup, horizontal sync works the same as vertical sync. Both are
generated by the Atari and latched onto by the TV. The only difference is
that the horizontal sync counter is in the TIA hardware while the vertical
sync counter is controlled in software.
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://stella.biglist.com
