See Figure 11-1 for a visual
description.
Active Lines Per Frame (ALPF)
Defines the number of lines in a frame containing displayable data. ALPF is
a subset of the TLPF.
Active Pixels Per Line (APPL)
Defines the number of pixel clocks in a line containing displayable data.
APPL is a subset of the TPPL.
Horizontal Back Porch (HBP) Blanking
Defines the number of blank pixel clocks after the active edge of horizontal
sync but before the first active pixel.
Horizontal Front Porch (HFP) Blanking
Defines the number of blank pixel clocks after the last active pixel but
before horizontal sync.
Horizontal Sync (HS or Hsync)
Timing reference point that defines the start of each horizontal interval
(line). The active edge of the HS signal defines the absolute reference
point. The active edge (either rising or falling edge as defined by the
source) is the reference from which all horizontal blanking parameters are
measured.
Total Lines Per Frame (TLPF)
Total number of active and inactive lines per frame; defines the vertical
period (or frame time).
Total Pixel Per Line (TPPL)
Total number of active and inactive pixel clocks per line; defines the
horizontal line period in pixel clocks.
Vertical Sync (VS or Vsync)
Timing reference point that defines the start of the vertical interval
(frame). The absolute reference point is defined by the active edge of the
VS signal. The active edge (either rising or falling edge as defined by the
source) is the reference from which all vertical blanking parameters are
measured.
Vertical Back Porch (VBP) Blanking
Defines the number of blank lines after the active edge of vertical sync but
before the first active line.
Vertical Front Porch (VFP) Blanking
Defines the number of blank lines after the last active line but before the
active edge of vertical sync.