LK404-25 Technical Manual Revision 2.0 PCB Revision: 2.0 or Higher Firmware Revision: 5.
Revision History Revision 2.
Contents 1 Introduction ............................................................................................................................................... 1 2 Quick Connect Guide.................................................................................................................................. 2 2.1 Available Headers ............................................................................................................................... 2 2.2 Standard Module ................
6.5 Dallas One-Wire ................................................................................................................................ 19 6.6 Keypad............................................................................................................................................... 20 6.7 Display Functions .............................................................................................................................. 22 6.8 Data Security .................................
1 Introduction Figure 1: LK404-25 Display The LK404-25 is an intelligent alphanumeric liquid crystal display designed to decrease development time by providing an instant solution to any project. RS232, TTL, and I2C protocols allow the LK404-25 to be connected to a wide variety of host controllers. Communication speeds of up to 115.2kbps for serial protocols and 100kbps for I2C ensure lightning fast display updates.
2 Quick Connect Guide 2.
2.2 Standard Module The standard version of the LK404-25 allows for user configuration of three common communication protocols. First, the unit can communicate using serial protocol at either RS323 or TTL voltage levels. Second, it can communicate using the Inter-Integrated Circuit connect, or I2C protocol. Connections for each protocol can be accessed through the four pin Communication/Power Header as outlined in the Serial Connections and I2C Connections sections below.
2. Make the connections. a. Connect the four pin female header of the Communication/Power Cable to the Communication/Power Header of your LK404-25. b. Insert the male end of your serial cable to the corresponding DB9 header of the Communication/Power Cable and the mate the female connector with the desired communication port of your computer. c. Select an unmodified floppy cable from a PC power supply and connect it to the power header of the Communication/Power Cable. 3. Create.
3 Software The multiple communication protocols available and simple command structure of the LK404-25 means that a variety of applications can be used to communicate with the display. Text is sent to the display as a character string, for example, sending the decimal value 41 will result in an 'A' appearing on the screen. A number of control characters are also activated. Commands are merely values prefixed with a special command byte, 254 in decimal.
This command allows raw bytes to be sent to the display, permitting many different formats for entry and displaying in decimal notation. Any command from this manual may be entered in decimal notation separated by slashes. /254/ /88/ Figure 5: uProject Command Again, the clear screen command is sent to a connected display, this time using uProject raw data command style. Scripts can be run as a whole using the execute command from the script menu, or as single commands by selecting execute once.
4 Hardware 4.1 Standard Model Communication/Power Header Table 4: Communication/Power Pinout Figure 6: Communication/Power Header Pin 1 2 3 4 Function Vcc Rx (SCL) Tx (SDA) Gnd The Communication/Power Header provides a standard connector for interfacing to the LK404-25. Voltage is applied through pins one and four of the four pin Communication/Power Header. Please ensure the correct voltage input for your display by referencing Voltage Specifications before connecting power.
Power Through DB9 Jumper In order to provide power through pin 9 of the DB-9 Connector you must connect the Power Through DB-9 Jumper labelled D, as illustrated below. This connection can be made using a zero ohm resistor, recommended size 0603, or a solder bridge. The LK404-25 allows all voltage models to use the power through DB-9 option, see the Voltage Specifications for power requirements.
4.2 Common Features General Purpose Outputs Table 6: GPO Pinout Figure 9: GPO Header Pin 1 2 3 4 5 6 7 Function GPO 1 GPO 2 GPO 3 GPO 4 GPO 5 GPO 6 Vcc Pin 8 9 10 11 12 13 14 Function Gnd Gnd Gnd Gnd Gnd Gnd Gnd A unique feature of the LK404-25 is the ability to control relays* and other external devices using either one or six General Purpose Outputs. Each can source up to 10mA of current at five volts when on or sink 20mA at zero volts when off.
Keypad Header Table 8: Keypad Pinout Figure 11: Keypad Header Pin 1 2 3 4 5 6 Function Gnd Row 1 Row 2 Row 3 Row 4 Row 5 Pin 7 8 9 10 11 12 Function Column 1 Column 2 Column 3 Column 4 Column 5 Gnd/Vcc* To facilitate user input, the LK404-25 provides a Keypad Interface Connector which allows a matrix style keypad of up to twenty-five keys to be directly connected to the display module. Key presses are generated when a short is detected between a row and a column.
5 Troubleshooting 5.1 Power In order for your LK404-25 to function correctly, it must be supplied with the appropriate power. If the power LED near the top right corner of the board is not illuminated, power is not applied correctly. Try following the tips below. First, make sure that you are using the correct power connector. Standard floppy drive power cables from your PC power supply may fit on the Communication/Power Header; however they do not have the correct pin out to provide power.
5.3 Communication When communication of either text or commands is interrupted, try the steps below. • • • • • • • • First, check the communication cable for continuity. If you don't have an ohm meter, try using a different communication cable. If you are using a PC try using a different Com Port. Next, please ensure that the display module is set to communicate on the protocol that you are using, by checking the Protocol Select Jumpers.
6 Commands 6.1 Communication 1.1 Change Baud Rate Dec 254 57 Speed Hex FE 39 Speed ASCII ■ 9 Speed Immediately changes the baud rate. Not available in I2C. Baud rate can be temporarily forced to 19200 by a manual override. Speed Byte Valid settings shown below. v5.0 Table 10: Accepted Baud Rate Values Rate Speed 1200 83 2400 41 4800 207 9600 103 19200 51 28800 34 38400 25 57600 16 *76800 12 *115200 8 *Note: Baud rates 76800 and 115200 added with the release of firmware revision 5.
6.2 Text 2.1 Clear Screen Dec 254 88 Hex FE 58 ASCII ■X Clears the contents of the screen. v5.0 2.2 Change the Start Up Screen Dec 254 64 Characters v5.0 Hex FE 40 Characters ASCII ■ @ Characters Changes the message displayed on start up. Custom characters can be included by adding their decimal value (07). Characters will automatically wrap on the display. Characters 80 bytes, space characters can be added as needed 2.3 Auto Scroll On Dec 254 81 v5.
2.8 Go Home Dec 254 72 Hex FE 48 ASCII ■H Returns the cursor to the top left of the screen. v5.0 2.9 Move Cursor Back Dec 254 76 Hex FE 4C ASCII ■L Moves cursor one position to the left. Cursor will obey wrap settings. v5.0 2.10 Move Cursor Forward Dec 254 77 Hex FE 4D ASCII ■M Moves cursor one position to the right. Cursor will obey wrap settings. v5.0 2.11 Underline Cursor On Dec 254 74 Hex FE 4A ASCII ■J Displays a line under the current cursor position. Can be used with block cursor. v5.0 2.
6.3 Special Characters 3.1 Create a Custom Character Dec 254 78 ID Data v5.0 Hex FE 4E ID Data ASCII ■ N ID Data Creates a custom character. Each character is divided into 8 rows of 5 pixels; each data byte represents one row. Each byte is padded by three zero bits followed by five bits representing each pixel state. A one represents an on condition while a zero is off. Characters are lost when a new memory bank is loaded, unless they are saved. ID Byte Character ID, value between 0 and 7.
3.4 Save Start Up Dec 254 194 ID Data v5.0 Screen Custom Hex FE C2 ID Data ■ ┬ ID Data Characters ASCII Saves a custom character to memory for the start up screen or repeated use. Start up characters are displayed by sending their ID to the screen. ID Byte Value between 0 and 7. Data Byte[8] Character pixel data, see Custom Degree Character example. 3.5 Initialize Medium Numbers Dec 254 109 v5.0 Hex FE 6D ASCII ■m Loads the medium number custom character bank into memory.
3.10 Place Horizontal Bar Graph Dec 254 124 Column Row Direction Length v5.0 Hex FE 7C Column Row Direction Length ■ | Column Row Direction Length ASCII Places a horizontal bar graph on the screen beginning at the column and row specified. The bar extends either right or left to the length indicated. New bars will overwrite old.
6.4 General Purpose Output 4.1 General Purpose Output On Dec 254 87 Number Hex FE 57 Number ASCII ■ W Number Turns the specified GPO on, sourcing current from an output of five volts. Number Byte GPO to be turned on. v5.0 4.2 General Purpose Output Off v5.0 Dec 254 86 Number Hex FE 56 Number ASCII ■ V Number Turns the specified GPO off, sinking current to an output of zero volts. Number Byte GPO to be turned off. 4.3 Set Start Up GPO State Dec 254 195 Number State v5.
5.2 Dallas One-Wire Transaction Dec 254 200 1 Flags Send Bits Receive Bits Data v5.0 Hex FE C8 01 Flags Send Bits Receive Bits Data ■ ╚ STX Flags Send Bits Receive Bits Data ASCII Performs a single Dallas 1-Wire transaction. Consult your device documentation for information regarding device specific protocols. If an error is encountered, a corresponding value will be returned by the device. Flags Byte Flags for transaction, see below. Send Bits Byte Number of bytes to be sent to the device.
6.4 Clear Key Buffer Dec 254 69 Hex FE 45 ASCII ■E Clears all key presses from the key buffer. v5.0 6.5 Set Debounce Time Dec 254 85 Time v5.0 Hex FE 55 Time ASCII ■ U Time Sets the time between a key press and a key read by the display. Most switches will bounce when pressed; the debounce time allows the switch to settle for an accurate read. Default is 8 representing approximately 52ms. Time Byte Debounce increment (debounce time = Time * 6.554ms). 6.6 Set Auto Repeat Mode Dec 254 126 Mode v5.
6.7 Display Functions 7.1 Backlight On Dec 254 66 Minutes v5.0 Hex FE 42 Minutes ASCII ■ B Minutes Turns the display backlight on for a specified length of time. If an inverse display color is used this command will essentially turn on the text. Minutes Byte Number of minutes to leave backlight on, a value of 0 leaves the display on indefinitely. 7.2 Backlight Off Dec 254 70 Hex FE 46 ASCII ■F Turns the display backlight off. If an inverse display colour is used this command will turn off the text. v5.
6.8 Data Security 8.1 Set Remember Dec 254 147 Switch v5.0 Hex FE 93 Switch ASCII ■ ô Switch Allows changes to specific settings to be saved to the display memory. Writing to non-volatile memory can be slow and each change consumes 1 write of at least 100,000 available. The Command Summary outlines which commands are saved always, never, and when this command is on only. Remember is off by default. Switch Byte 1 for on or 0 for off. 8.2 Set Data Lock Dec 254 202 245 160 Level v5.
6.9 Miscellaneous 9.1 Write Customer Data Dec 254 52 Data v5.0 Hex FE 34 Data ASCII ■ 4 Data Saves a user defined block of data to non-volatile memory. Useful for storing display information for later use. Data Byte [16] User defined data. 9.2 Read Customer Data Dec 254 53 v5.0 Hex FE 35 ASCII ■5 Reads data previously written to non-volatile memory. Data is only changed when written, surviving power cycles. Response Byte [16] Previously saved user defined data. 9.
7 Appendix 7.1 Command Summary Available commands below include identifying number, required parameters, the returned response and an indication of whether settings are remembered always, never, or with remember set to on.
Table 23: Special Character Command Summary Name Create a Custom Character Save Custom Characters Load Custom Characters Save Start Up Screen Custom Characters Initialize Medium Numbers Place Medium Numbers Initialize Large Numbers Place Large Numbers Initialize Horizontal Bar Place Horizontal Bar Graph Initialize Narrow Vertical Bar Initialize Wide Vertical Bar Place Vertical Bar Dec 78 193 192 Hex 4E C1 C0 ASCII N ñ └ Parameters Byte[9] Byte[10] Byte Response None None None Remembered Remember On A
Table 27: Display Functions Command Summary Name Backlight On Backlight Off Set Brightness Set and Save Brightness Set Contrast Set and Save Contrast Dec 66 70 153 152 80 145 Hex 42 46 99 98 50 91 ASCII B F Ö ÿ P æ Parameters Byte None Byte Byte Byte Byte Response None None None None None None Remembered Remember On Remember On Remember On Always Remember On Always Table 28: Data Security Command Summary Name Set Remember Set Data Lock Set and Save Data Lock Dec 147 202, 245, 160 203, 245, 160 He
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7.3 Block Diagram Figure 13: Functional Diagram 7.4 Environmental Specifications Table 30: Environmental Limits Standard Extended (-E) 0°C to +50°C -20°C to +70°C -10°C to +60°C -30°C to +80°C Maximum 90% non-condensing Maximum 10°C /min Operating Temperature Storage Temperature Operating Relative Humidity Thermal Shock 7.
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7.7 Optical Characteristics Table 34: Display Optics Module Size Viewing Area Active Area Character Size Character Pitch Pixel Size Pixel Pitch Viewing Direction Viewing Angle Backlight Half-Life 190.00 x 54.00 x 27.0 148.0 x 42.9 140.45 x 30.30 2.78 x 4.89 3.53 x 6.09 0.50 x 0.55 0.57 x 0.62 12 -30 to +30 100,000 mm mm mm mm mm mm mm O’clock ° Hours 8 Ordering 8.1 Part Numbering Scheme Table 35: Part Numbering Scheme LK 1 -404 2 -25 3 4 -VPT 5 6 -E 7 8.
8.3 Accessories Power Table 37: Power Accessories PCS Standard Power Cable Communication Table 38: Communication Accessories CSS1FT 1 ft. Serial Cable CSS4FT 4 ft.
9 Definitions ASCII: American standard code for information interchange used to give standardized numeric codes to alphanumeric characters. BPS: Bits per second, a measure of transmission speed. DOW: Dallas One-Wire protocol, similar to I2C, provides reduced data rates at a greater distance. One wire carries data, while two others supply power and ground. Matrix Orbital tests non-parasitic devices only, those that do not draw power from the data line; however, some parasitic devices may work.
