2 Matching Annotations
  1. Sep 2024
    1. TELEVISION PROTOCOL
      • TV picture: 60fps, each frame drawn line by line
      • 1 frame (Atari's research data for max TV compat)
      • 262/312 lines, 228 clocks per line
      • 3 x VSYNC + 37/45 x VBLANK + 192/228 display + 30/36 overscan
      • VSYNC = signal TV to start new frame
      • VBLANK = ?
      • overscan = ?
      • 1 line = 68 cycle horizontal blank + 160 cycle display
      • horizontal timing handled by TIA
      • WSYNC stops CPU till start of next line
      • vertical timing by CPU
      • after completion of a frame => VSYNC + VBLANK + pic + VBLANK
      • 1 CPU cycle = 3 TIA cycle
      • TV pic
      • drawn line at a time
      • CPU put data for line into TIA, TIA convert data to video signals
      • TIA has data only for current line
      • 70/85 blank lines for game logic
  2. Feb 2021