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Registers
1066
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Liquid Crystal Display Controller (LCDC)
23.3.10 LCD Raster Timing Register 1 (RASTER_TIMING_1)
The LCD raster timing 1 register (RASTER_TIMING_1) contains four bit-fields that are used as modulus
values for a collection of down counters, each of which performs a different function to control the timing
of several of the LCD’s pins. The (RASTER_TIMING_1 is shown in
and described in
.
Figure 23-31. LCD Raster Timing Register 1 (RASTER_TIMING_1)
31
24
23
16
VBP
VFP
R/W-0
R/W-0
15
10
9
0
VSW
LPP
R/W-0
R/W-0
LEGEND: R = Read only; -
n
= value after reset
Table 23-21. LCD Raster Timing Register 1 (RASTER_TIMING_1) Field Descriptions
Bit
Field
Value
Description
31-24
VBP
0-FFh
Vertical Back Porch. Encoded value (VBP) used to specify number of line clock (LCD_HSYNC) periods to
add to the beginning of a frame before the first set of pixels is output to the display. Note that line clock
transitions during the insertion of the extra line clock periods.
23-16
VFP
0-FFh
Vertical Front Porch. Encoded value (VFP) used to specify number of line clock (LCD_HSYNC) periods to
add to the end of each frame. Note that the line clock transitions during the insertion of the extra line clock
periods.
15-10
VSW
0-3Fh
Vertical Synchronization Pulse Width.
In TFT mode, encoded value (VSW + 1) defines the number of line clock (LCD_HSYNC) cycles to hold
the frame clock (LCD_VSYNC) active.
In STN mode, encoded value (VSW + 1) specifies the number of extra line clock (LCD_HSYNC) cycles to
be inserted after the vertical front porch (VFP) period has elapsed.
9-0
LPP
0-3FFh
Lines per Panel. Encoded value (LPP + 1) used to specify number of lines per panel. It represents the
total number of lines on the LCD.
23.3.10.1 Lines Per Panel (LPP)
NOTE:
LPP must be programmed to the value required minus 1 (C7h for 200 lines per panel).
The lines per panel (LPP) bit-field is used to specify the number of lines or rows per LCD panel being
controlled. It represents the total number of lines for the entire LCD display (the screen height). LPP is a
10-bit value, which represents between 1–1024 lines per panel. LPP is used to count the correct number
of line clocks that must occur before the frame clock can be pulsed.