DS508UM1
97
6.17
LCD Registers
6.17.1
LCDCON — LCD Control Register
ADDRESS: 0x8000.02C0
The LCD control register is a 32-bit read / write register that controls the size of the LCD screen and
the operating mode of the LCD controller. Refer to the system description of the LCD controller for
more information on video buffer mapping
.
The LCDCON register should only be reprogrammed when the LCD controller is disabled.
17-18
WRDLEN: This two bit field selects the word length according to the table below.
Bit
Description
Table 52. UBRLCR1-2 UART1-2
(cont.)
WRDLEN
Word Length
00
5 bits
01
6 bits
10
7 bits
31
30
29-25
24-19
18-13
12-0
GSMD2
GSMD1
AC prescale
Pixel prescale
Line length
Video buffer size
Bit
Description
0-12
Video buffer size: The video buffer size field is a 13-bit field that sets the total number of bits x
128 (quad words) in the video display buffer. This is calculated from the formula:
Video buffer size = (Total bits in video buffer / 128) – 1
i.e., for a 640 x 240 LCD and 4 bits-per-pixel, the size of the video buffer is equal to 614400 bits.
Video buffer = 640 x 240 x 4=614400 bits
Video buffer size field = (614400 / 128) – 1 = 4799 or 0x12BF hex.
The minimum value allowed is 3 for this bit field.
13-18
Line length: The line length field is a 6-bit field that sets the number of pixels in one complete
line. This field is calculated from the formula:
line length = (Number of pixels in line / 16) – 1
i.e., for 640 x 240 LCD Line length = (640 / 16) – 1 = 39 or 0x27 hex.
The minimum value that can be programmed into this register is a 1 (i.e., 0 is not a legal value).
Table 53. LCDCON
Summary of Contents for EP7312
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