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Auto Size Registers
(Continued)
Horizontal Flyback or Sync Duration:
HF_S1 (0x8583)
Reserved
RSV
RSV
HF_S0 (0x8582)
Horizontal Flyback or Sync Duration
HFL_HS[9:0]
RSV
RSV
RSV
RSV
Bits 9–0
This is a 10-bit wide register that records the measured value of the horizontal flyback or sync
during video detect. When no video is detected, this register should return a value of zero. Once
measurement is completed and the auto size enable bit has cleared itself back to 0, the measured
data is ready to be read by the microcontroller. Reading this register before that may give
erroneous results. This register resets to default values, ready to record new measured values
when the auto size enable bit is set again.
Horizontal Back Porch Duration:
H_BP1 (0x8585)
H_BP0 (0x8584)
Reserved
RSV
Horizontal Back Porch Duration
HBP[10:0]
RSV
RSV
RSV
RSV
Bits 10–0
This is an 11-bit wide register that records the lowest measured value of the horizontal back porch
during video detect. When no video is detected, the sum of this register and the horizontal flyback
or sync should be within 1 pixel of the total number of pixels per line. Once measurement is
completed and the auto size enable bit has cleared itself back to 0, the measured data is ready to
be read by the microcontroller. Reading this register before that may give erroneous results. This
register resets to default values, ready to record new measured values when the auto size enable
bit is set again.
Vertical Front Porch Duration:
V_FP1 (0x8587)
Reserved
RSV
RSV
V_FP0 (0x8586)
Vertical Front Porch Duration
VFP[10:0]
RSV
RSV
RSV
Bits 10–0
This is an 11-bit wide register that records the lowest measured value of the vertical front porch in
terms of horizontal line periods during video detect. When no video is detected, this register should
return a value of zero. Once measurement is completed and the auto size enable bit has cleared
itself back to 0, the measured data is ready to be read by the microcontroller. Reading this register
before that may give erroneous results. This register resets to default values, ready to record new
measured values when the auto size enable bit is set again.
Vertical Sync Duration:
V_SYN_D (0x8588)
Vertical Flyback or Sync Duration
VSYNC[7:0]
Bits 7–0
This is an 8-bit wide register that records the measured value of the vertical flyback or sync in
terms of horizontal line periods during video detect. Once measurement is completed and the auto
size enable bit has cleared itself back to 0, the measured data is ready to be read by the
microcontroller. Reading this register before that may give erroneous results. This register resets to
default values, ready to record new measured values when the auto size enable bit is set again.
Vertical Back Porch Duration:
V_BP1 (0x858A)
V_BP0 (0x8589)
Reserved
RSV
Vertical Back Porch Duration
VBP[10:0]
RSV
RSV
RSV
RSV
L
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