Spartan-3A/3AN FPGA Starter Kit Board User Guide
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47
UG334 (v1.1) June 19, 2008
LCD Controller
R
The character ROM contains the ASCII English character set and Japanese katakana
characters.
The controller also provides for eight custom character bitmaps, stored in
CG RAM
. These
eight custom characters are displayed by storing character codes 0x00 through 0x07 in a
DD RAM
location.
CG RAM
The Character Generator RAM (CG RAM) provides space to create eight custom character
bitmaps. Each custom character location consists of a 5-dot by 8-line bitmap, as shown in
Figure 5-5
.
The
Set CG RAM Address
command initializes the address counter before reading or
writing to CG RAM. Write CG RAM data using the
Write Data to CG RAM or DD RAM
command, and read CG RAM using the
Read Data from CG RAM or DD RAM
command.
Figure 5-4:
LCD Character Set
Lo
wer Data Nibb
le
Upper Data Nibble
DB7
DB6
DB5
DB4
DB3 DB2 DB1 DB0
UG230_c5_02_030306