Matrix Orbital LCD2041 User manual

LCD2041
Technical Manual
Revision: 2.0

Contents
Contents ii
1 Introduction 1
1.1 What to Expect From the LCD2041 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 What Not to Expect From the LCD2041 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3 SetupforTesting ........................................ 1
1.4 TryingouttheLCD2041 .................................... 2
2 Connections 2
2.1 ConnectorPinout ........................................ 2
2.1.1 PowerConnection ................................... 3
2.1.2 FiveVoltModules ................................... 4
2.1.3 Wide Voltage Range Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.4 Applying Power through the DB-9 Connector . . . . . . . . . . . . . . . . . . . . 6
2.2 RS-232Communications.................................... 6
2.2.1 DB9Connections.................................... 6
2.2.2 Alternate Serial Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2.3 TTLcommunications ................................. 8
2.2.4 Configuring RS-232 and I2C ............................. 8
2.3 I2CCommunications ...................................... 10
2.3.1 ACK .......................................... 10
2.4 GeneralPurposeOutput..................................... 11
3 Displaying Text 12
3.1 General ............................................. 13
3.2 ThebuiltinCharacterFont................................... 13
3.3 WritingTexttotheDisplay................................... 14
3.4 TextCommands......................................... 14
3.4.1 Auto line wrap on (254 67) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.4.2 Auto line wrap off (254 68) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.4.3 Autoscrollon(25481) ................................ 14
3.4.4 Autoscrolloff(25482) ................................ 14
3.4.5 Set cursor position (254 71 [column] [row]) . . . . . . . . . . . . . . . . . . . . . . 15
3.4.6 Send cursor home (254 72) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.4.7 Turn on underline cursor (254 74) . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.4.8 Turn off underline cursor (254 75) . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.4.9 Turn on block (blinking) cursor (254 83) . . . . . . . . . . . . . . . . . . . . . . . 15
3.4.10 Turn off block (blinking) cursor (254 84) . . . . . . . . . . . . . . . . . . . . . . . 15
3.4.11 Cursorleft(25476)................................... 15
3.4.12 Cursorright(25477).................................. 16
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4 Bar Graphs and Special Characters 16
4.1 CommandList ......................................... 16
4.1.1 Initialize wide vertical bar graph (254 118) . . . . . . . . . . . . . . . . . . . . . . 16
4.1.2 Initialize narrow vertical bar graph (254 115) . . . . . . . . . . . . . . . . . . . . . 16
4.1.3 Draw vertical bar graph (254 61 [column] [height]) . . . . . . . . . . . . . . . . . . 16
4.1.4 Initialize horizontal bar graph (254 104) . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1.5 Draw horizontal bar graph (254 124 [column] [row] [dir] [length]) . . . . . . . . . . 17
4.1.6 Initialize large digits (254 110) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1.7 Place large digit 254 35 [col] [digit] . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1.8 Define custom character (254 78 [c] [8 bytes]) . . . . . . . . . . . . . . . . . . . . 17
5 Miscellaneous Commands 19
5.1 CommandList ......................................... 19
5.1.1 Cleardisplay(25488) ................................. 19
5.1.2 Set contrast (254 80 [contrast]) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.1.3 Backlight on (254 66 [minutes]) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.1.4 Backlightoff(25470) ................................. 19
5.1.5 General purpose output off (254 86) . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.1.6 Set backlight brightness (254 153 [brightness]) . . . . . . . . . . . . . . . . . . . . 20
5.1.7 General purpose output on (254 87) . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5.1.8 Readmoduletype ................................... 20
6 Appendix; Command Summary 20
6.1 General ............................................. 20
6.2 IssuingCommands ....................................... 20
6.3 OnNumbers........................................... 21
6.3.1 ASCIICharacters.................................... 21
6.4 TextCommands......................................... 22
6.5 Bar Graphs and Special Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.6 MiscellaneousCommands ................................... 25
7 Appendix: Specifications 26
7.1 Specifications.......................................... 26
7.2 Options ............................................. 28
8 Appendix: Glossary 28
Matrix Orbital LCD2041 iii

1 Introduction
The LCD2041 comes equipped with the following features;
•20 column by 4 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
•Communication over RS-232 or I2C
•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 +8V to +15V
•Extended temperature option
•Fits Matrix Orbital’s Dual PC Bay insert without any modifications
1.1 What to Expect From the LCD2041
The LCD2041 is designed as the display unit for an associated controller. The controller may be anything
from a single board, special purpose micro-controller to a PC, depending on the application. This controller
is responsible for what is displayed on the screen of the display.
The display 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 Not to Expect From the LCD2041
The display does not include bitmap graphics capability, except that permitted by defining special char-
acters. The display does not include a keypad interface.
1.3 Setup for Testing
Before setting up the application the user may want to try out the display. This is easily done with a PC.
If not equipped with a dual bay PC mounting kit, the following will be required;
•A 4-pin power connector of the type used to connect 3.5” floppy drive. Take care not to connect the
display to an unmodified spare power connector in a PC
•A spare RS-232 port. (Either COM1 or COM2)
•A 5V power supply. For wide voltage models, an 8 - 15 V supply will be required
•A 9 or 25 pin RS-232 serial cable. If using a 25 conductor cable, a 9 to 25 pin adapter will be required
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Figure 1: Connections for Testing
1. Refer to the Figure above for the following steps.
2. Wire the connector to the power supply. On most connectors the RED lead will go to +5V and the
BLACK lead to GND.
NOTE The Manufacturer’s Warranty becomes void if the unit is subjected to over-voltage
or reversed polarity.
3. Connect the display to the PC using the serial cable and adapter if required. Make sure the RS-232
cable includes the required ground lead. There must be no voltage differential between the RS-232
ground and the power supply ground.
4. Connect the power connector, making sure that the +5V goes to V+ . Turn on the power; the display
backlight should come on and a blinking cursor at the top left should appear.
1.4 Trying out the LCD2041
The unit should be connected to power and the PC and backlight should be on. To experiment with
typing text, run a PC program such as Display Tuner or AlphaDemo. Make sure it’s configured to use the
correct port. Set the baud rate to 19,200.
To exercise some of the other features of the display, a program (in any convenient language such as
Basic or C) will need to be written in order to issue the required command strings. Most terminal programs
are unable to issue the 0xFE character needed as a command prefix.
2 Connections
2.1 Connector Pinout
Refer to the Figure below for this chapter.
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Figure 2: Electrical Connections
The display has three connectors;
Table 1: Connectors & Functions
Connector Function
2 pin General purpose output
4 pin Power and I2C communication
DB-9F RS-232/power
2.1.1 Power Connection
Power is applied via pins 1 and 4. Power requirement for standard units is +5 VDC ±0.25V . Units with
the wide voltage range option require 8 - 15 VDC.
WARNINGS
•Do not apply any power with reversed polarization. Do not apply
any voltage other than the specified voltage. Do not use any cables
other than the cables supplied by Matrix Orbital, unless aware of
the modifications required. Do not apply voltage to the DB-9 con-
nector AND power connector Do not apply more than +5Vdc to
pin #9 on the DB-9 connector.
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Connector pinout is as follows;
Figure 3: Power Connector
Table 2: Pinout Connections
Pin 4 Ground
Pin 3 SDA (I2C data) / Rx
Pin 2 SCL (I2C clock) / Tx
Pin 1 Vdc
2.1.2 Five Volt Modules
If the display is used in a PC it is tempting to plug a spare power connector into the unit. Don’t do this!
Wiring for the PC power connector and that required for the display are different.
Figure 4: Wiring for 5V Modules
Matrix Orbital is equipped to supply an adapter cable designed to use with the LCD2041 when it’s
installed in a PC. The cable is wired as shown in the Figure below.
NOTE This cable does not provide connections for I2C.
Matrix Orbital LCD2041 4

Figure 5: Five Volt Power Cable
2.1.3 Wide Voltage Range Modules
NOTE Do not use this cable unless the display module has the "Wide voltage range"
option. Use of the 12 volt power cable with 5 volt modules will damage the module.
The 12 volt power cable is designed for use with wide voltage range display modules mounted in a PC.
Wiring required for the 12 volt power connector is shown in the Figure below.
Figure 6: Wiring for 12 Volt Modules
Matrix Orbital is equipped to supply an adapter cable designed to use with the display module when it’s
installed in a PC. The cable is wired as shown in the Figure below.
Figure 7: Twelve Volt Power Cable
Matrix Orbital LCD2041 5

2.1.4 Applying Power through the DB-9 Connector
Power may be provided to the module by pin 9 of the DB-9 connector instead of through the 4-pin SIP.
If power is to be applied using the DB-9, it must be a regulated 5Vdc supply.
NOTE This applies to wide voltage units, V and VPT extensions, as well as to standard
5 volt units.
Figure 8: DB-9 Power
To use pin 9 as the power source, the user must solder the 5 volt jumper pad beside the DB-9 connector.
WARNING Application of a voltage to pin 9 greater than 5.25 volts
may cause immediate destruction of unit and void the Manufacturer’s
Warranty.
2.2 RS-232 Communications
The RS-232 connector on the PC cable is wired so that a standard ’straight through’ 9 pin D-sub cable
may be used to connect the module to a standard serial port such as COM ports on PCs. Please note that this
device complies with the EIA-232 standard in that it uses signal levels from ±12V to ±12V and can be
converted to TTL levels as well. The display is set at 19.2Kbps default speed. Other settings are;
•8 bits, no parity, 1 stop bit.
2.2.1 DB9 Connections
A standard DB-9F is provided for RS-232 communications. Power may also be supplied via this con-
nector if desired.
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Figure 9: RS-232 and Power Connector
Table 3: RS-232 Pinout
Pin Number Direction Description LCD Host
2 Data from LCD Data out (LCD Tx Rx
3 Data to LCD Data in (LCD) Rx Tx
5 - Ground gnd gnd
2.2.2 Alternate Serial Connection
An optional alternate connection header is provided to allow one cable for data and power. Two jumpers
will have to be set into the RS-232 position above the DB-9 connector.
Figure 10: RS232 Configuration
Connector pinout is as follows;
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