Matrix Orbital LCD0821 Legacy - Manual (Page 4)

LCD0821 rev 2 4
1. Introduction
Your LCD0821 has the following features:
8 column by 2 line text display
Built-in font with provision for up to 8 user-defined characters
Speeds from 1200 bps to a lighting fast 19.2 Kbps over RS-232
Communicate over RS-232 or I²C
Use up to 16 modules on the same 2-wire I 2 C interface
Software controlled contrast
Backlight with configurable time-out setting up to 180 minutes
One general purpose output for a variety of applications
Horizontal or Vertical bar graphs
Variable power options, +5V or +7V to +15V
Extended temperature option.
1.1 What it Does
The LCD0821 is designed as the display unit for an associated controller. The controller may be anything
from a single board, special purpose microcontroller to a PC, depending on the application. This controller
is responsible for what you see on the screen of the LCD0821.
The LCD0821 provides a simple command structure to allow text and bar graphs to be displayed on the
screen. Text fonts are built in, and use standard ASCII mapping. Provision is made for up to 8 user-defined
characters.
The screen is backlit for low-light situations. Backlighting may be turned on or off under program control.
Contrast is adjustable to compensate for differing lighting conditions and viewing angles.
A general purpose output allows the controller to switch an electronic or electro-mechanical device by
issuing commands to the display unit. This can be used for controlling LEDs, relays, etc.
1.2 What it Does Not Do
The LCD0821 does not include bitmap graphics capability, except that permitted by defining special
characters. The LCD0821 does not include a keypad interface.
1.3 Setup for Testing
Before setting up your application you may want to try out the LCD0821. This is easily done with a PC.
Here's what you'll need:
A power cable with a 4 pin connector (same connector as used to connect a 3.5 inch floppy
drive). Do not connect the LCD0821 to an unmodified spare power connector in a PC. To
modify such a cable see section 2.1.1.
A 5 V power supply (for wide voltage models an 8 – 15 V supply is required).
a PC with a spare RS-232 port (COM1 or COM2).
A modified 9 or 25 pin RS-232 serial cable.
Figure 1-1 Connections for Testing