Cirrus Logic AN269 - Manual (Page 54)

54 AN269REV1
AN269
HActiveStop = HBlankStop
HActiveStop = 22
Since no clock gating is required, the HClkStart should be set to HClkTotal and HClkStop should be set to HClkStop
to HClkTotal + 1
HClkStart = HClkTotal
HClkStart = 799
HClkStart = HClkTotal + 1
HClkStop = 800
Now, the vertical timing register settings can be determined. Using the equations from “Vertical Alignment Signals”
on page 22 , the following values are obtained:
VLinesTotal = tVERT – 1
VLinesTotal = 525 - 1 = 524
VSyncStart = VLinesTotal
VSyncStart = 524
VSyncStop = VLinesTotal – tVSYNC
VSyncStop = 524 - 2 = 522
VBlankStart = VLinesTotal - tVSYNC - tVBACKPORCH
VBlankStart = 524 - 2 - 33 = 489
VBlankStop = tVFRONTPORCH - 1
VBlankStop = 9
VActiveStart = VBlankStart
VActiveStart = 489
VActiveStop = VBlankStop
VActiveStop = 9
Again, no clock gating is required, so we can set VClkStart to VLinesTotal and VClkStop to VLinesTotal+1:
VClkStart = VLinesTotal = 524
VClkStop = VLinesTotal + 1 = 525