Chapter 5: Character Lcd Screen; Overview - Xilinx Spartan-3E User Manual

R
Character LCD Screen

Overview

The Spartan-3E Starter Kit board prominently features a 2-line by 16-character liquid
crystal display (LCD). The FPGA controls the LCD via the 4-bit data interface shown in
Figure
4-bit data interface to remain compatible with other Xilinx development boards and to
minimize total pin count.
Once mastered, the LCD is a practical way to display a variety of information using
standard ASCII and custom characters. However, these displays are not fast. Scrolling the
display at half-second intervals tests the practical limit for clarity. Compared with the
50 MHz clock available on the board, the display is slow. A PicoBlaze processor efficiently
controls display timing plus the actual content of the display.
Spartan-3E Starter Kit Board User Guide
UG230 (v1.0) March 9, 2006
5-1. Although the LCD supports an 8-bit data interface, the Starter Kit board uses a
Spartan-3E FPGA
(M15)
(P17)
(R16)
(R15)
(M18)
(L18)
(L17)
Figure 5-1: Character LCD Interface
www.xilinx.com
Character LCD
390Ω
SF_D<11>
DB7
390Ω
SF_D<10>
DB6
390Ω
SF_D<9>
DB5
390Ω
SF_D<8>
DB4
DB[3:0]
LCD_E
E
LCD_RS
RS
LCD_RW
R/W
Intel StrataFlash
D[11:8]
'1'
SF_CE0 CE0
Chapter 5
Four-bit data
interface
Unused
UG230_c5_01_022006
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