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Auto Size Registers
(Continued)
Bits 10–0
This is an 11-bit wide register that records the lowest measured value of the vertical back porch in
terms of horizontal line periods during video detect. When no video is detected, the sum of this
register and the vertical flyback or sync should be within 1 line of the total number of lines per
field. 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.
Previous Field Vertical Front Porch Duration:
PREV_V_BP1 (0x858C)
Reserved
RSV
RSV
PREV_V_BP0 (0x858B)
Previous Vertical Front Porch Duration
VFP PREV[10:0]
RSV
RSV
RSV
Bits 10–0
This is an 11-bit wide register that retains the previous lowest measured value of the vertical front
porch during video detect in horizontal line periods from the previous field. It is used when interlace
mode is present, in order to accurately determine the correct parameter value for the frame. When
no video is detected, this register should return a value of zero. Reading this register within less
than one complete field period after the Video Detect Reset may give erroneous results. This
register resets to zero after the Video Detect Reset has been written.
Previous Field Vertical Sync Duration:
V_SYN_PREV (0x858D)
Previous Vertical Sync Duration
VSYNC PREV[7:0]
Bits 7–0
This is an 8-bit wide register that records the previous measured value of the vertical sync during
video detect in horizontal line periods from the previous field. It is used when interlace mode is
present, in order to accurately determine the correct parameter value for the frame. Reading this
register within less than one complete field period after the Video Detect Reset may give
erroneous results. This register resets to zero after the Video Detect Reset has been written.
Previous Vertical Back Porch Duration:
PREV_V_BP1 (0x858F)
Reserved
RSV
RSV
PREV_V_BP0 (0x858E)
Previous Vertical Back Porch Duration
VBP PREV[10:0]
RSV
RSV
RSV
Bits 10–0
This is an 11-bit wide register that records the previous lowest measured value of the vertical back
porch during video detect in horizontal line periods from the previous field. It is used when interlace
mode is present, in order to accurately determine the correct parameter value for the frame. When
no video is detected, this sum of this register and the VSYNC should be with 1 line of the total
number of lines per field. Reading this register within less than one complete field period after the
Video Detect Reset may give erroneous results. This register resets to zero after the Video Detect
Reset has been written.
HiBrite Control Register:
HB CONTROL (0x8590)
FSHEN
INTR_EN
LIMIT
WHDIS
RSV
RSV
RSV
RSV
Bits 3–0
Bit 4
Reserved and should be set to zero.
This bit must be low for the device to display HiBrite Software driven windows. This bit must be set
high for Full Screen HiBrite by the MCU.
Bits 4 and 5 must be both high for Full Screen
HiBrite.
This bit when set high will enable the Full Screen Hi-Brite feature. This bit can be used by the
MCU to highlight the entire screen without the use of the HiBrite software.
This bit must be set to 1 at all times for proper color bar communication.
Bit 5
Bit 6
L
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