LK162A-4T Including the LK162A-4T-USB varia nt Technical Manual Revision 1.1 PCB Revision: 1.0 or Higher Firmware Revision: 7.
Revision History Revision 1.1 1.
Contents 1 Introduction ............................................................................................................................................... 1 2 Quick Connect Guide.................................................................................................................................. 2 2.1 Available Headers ............................................................................................................................... 2 2.2 Standard Module ................
6.4 General Purpose Output ................................................................................................................... 17 6.5 Keypad............................................................................................................................................... 18 6.6 Display Functions .............................................................................................................................. 21 6.7 Data Security .......................................
1 Introduction Figure 1: LK162A-4T Display The LK162A-4T is an intelligent alphanumeric liquid crystal display designed to decrease development time by providing an instant solution to any project. In addition to the RS232, TTL and I2C protocols available in the standard model, the USB communication model allows the LK162A-4T 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 LK162A-4T 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 LK162A-4T. 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.
2.3 USB Module The LK162A-4T-USB offers a single USB protocol for an easy connection to a host computer. This simple and widely available protocol can be accessed using the on-board keyed, friction lock style USB connector as outlined in the USB Connections section. Recommended Parts The Four Pin USB cable is recommended for the LK162A-4T-USB display. It will connect to the keyed, friction lock style header on the unit and provide a connection to a regular A style USB connector, commonly found on a PC.
3 Software The multiple communication protocols available and simple command structure of the LK162A-4T 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 6: 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 7: 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 LK162A-4T. 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.
4.2 USB Model Four Pin USB Header Table 5: USB Pinout Pin 1 2 3 4 Figure 8: Four Pin USB Header Function GND D+ DVcc The LK162A-4T-USB comes with a keyed, friction lock style USB connector to fulfill both communication and power needs. This special header requires a CBL-USBA24PIN3FT cable. Most commonly used with a PC, this connection creates a virtual com port that offers a simple power solution with a familiar communication scheme. 4.
5 Troubleshooting 5.1 Power In order for your LK162A-4T 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/USB 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. v7.2 Table 8: 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 2 1.2 Change I C Slave Address Dec 254 51 Address v7.
1.5 Software Reset Dec 254 253 77 79 117 110 v8.4 Hex FE FD 4D 4F 75 6E ASCII ■²MOun Reset the display as if power had been cycled via a software command. No commands should be sent while the unit is in the process of resetting; a response will be returned to indicate the unit has successfully been reset. Response Short Successful reset response, 254 212. 6.2 Text 2.1 Clear Screen Dec 254 88 Hex FE 58 ASCII ■X Clears the contents of the screen. v7.2 2.
2.7 Set Cursor Position Dec 254 71 Column Row Hex FE 47 Column Row ASCII ■ G Column Row Sets the cursor to a specific cursor position where the next transmitted character is printed. Column Byte Value between 1 and number of character columns. Row Byte Value between 1 and number of character rows. v7.2 2.8 Go Home Dec 254 72 Hex FE 48 ASCII ■H Returns the cursor to the top left of the screen. v7.2 2.9 Move Cursor Back Dec 254 76 Hex FE 4C ASCII ■L Moves cursor one position to the left.
6.3 Special Characters 3.1 Create a Custom Character Dec 254 78 ID Data v7.2 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 v7.2 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 v7.2 Hex FE 6D ASCII ■m Loads the medium number custom character bank into memory.
3.9 Initialize Narrow Vertical Bar Dec 254 115 Hex FE 73 ASCII ■s Loads the narrow horizontal bar graph custom character bank into memory. A narrow bar is 2 pixels wide. Horizontal bar characters must be initialized before a graph is displayed. v7.2 3.10 Initialize Wide Vertical Bar Dec 254 118 v7.2 Hex FE 76 ASCII ■v Loads the wide horizontal bar graph custom character bank into memory. A wide bar is 5 pixels wide. Horizontal bar characters must be initialized before a graph is displayed. 3.
LED Indicators The LK162A-4T has 6 General Purpose Outputs which control 3 bi-colour LEDs. Red, green, and orangeyellow colours can be created using these software controlled GPOs. Odd numbered GPOs control red while even numbers switch the green aspects of the LEDs, as shown in the table below. Table 11: LED Output Colour Yellow Green Red Off GPOO 0 0 1 1 GPOE 0 1 0 1 4.4 Set LED Indicators Dec 254 90 Number Colour v8.
5.3 Poll Key Press Dec 254 38 v7.2 Hex FE 26 ASCII ■& Reads the last unread key press from the 10 key display buffer. If another key is stored in the buffer the MSB will be 1, the MSB will be 0 when the last key press is read. If there are no stored key presses a value of 0 will be returned. Auto transmit key presses must be turned off for this command to be successful. Response Byte Value of key pressed (MSb determines additional keys to be read). 5.
5.8 Assign Keypad Codes Dec 254 213 Key Down Key Up v7.2 Hex FE D5 Key Down Key Up ■ ╒ Key Down Key Up ASCII Assigns the key down and key up values sent to the host when a key press is detected. A key up and key down value must be sent for every key, a value of 255 will leave the key unaltered. Defaults are shown below. Key Down Bytes [4] Key down values, beginning at row one column one moving right then down. Key Up Bytes [4] Key up values, beginning at row one column one moving right then down.
6.6 Display Functions 6.1 Backlight On Dec 254 66 Minutes v7.2 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. 6.2 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. v7.
6.7 Set and Save Contrast Dec 254 145 Contrast v7.2 Hex FE 91 Contrast ASCII ■ æ Contrast Immediately sets and saves the contrast between background and text. Although contrast can be changed using the set command, it is reset to this saved value on start up. Default is 128. Contrast Byte Contrast level from 0(Light) to 255(Dark). 6.7 Data Security 7.1 Set Remember Dec 254 147 Switch v7.2 Hex FE 93 Switch ASCII ■ ô Switch Allows changes to specific settings to be saved to the display memory.
6.8 Miscellaneous 8.1 Write Customer Data Dec 254 52 Data v7.2 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. 8.2 Read Customer Data Dec 254 53 v7.2 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. 8.
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 19: 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 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 Always Never 194 C2 ┬ Byte[9] None Alway
Table 22: Display Functions Command Summary Name Backlight On Backlight Off Set Brightness Set and Save Brightness Set Backlight Colour Set Contrast Set and Save Contrast Dec 66 70 153 152 130 80 145 Hex 42 46 99 98 82 50 91 ASCII B F Ö ÿ é P æ Parameters Byte None Byte Byte Byte[3] Byte Byte Response None None None None None None None Remembered Remember On Remember On Remember On Always Remember On Remember On Always Table 23: Data Security Command Summary Name Set Remember Set Data Lock Set and
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7.3 Block Diagram Figure 13: Functional Diagram 7.4 Environmental Specifications Table 25: Environmental Limits Operating Temperature Storage Temperature Operating Relative Humidity Thermal Shock 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 7.
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7.7 Optical Characteristics Table 29: Display Optics Module Size Viewing Area Active Area Character Size Character Pitch Pixel Size Pixel Pitch Viewing Direction Viewing Angle Contrast Ratio Backlight Half-Life 96.40 x 23.00 x 31.14 51.6 x 11.9 48.2 x 8.9 2.45 x 3.95 3.05 x 4.95 0.45 x 0.45 0.50 x 0.50 12 -30 to +30 3 50,000* mm mm mm mm mm mm mm O’clock ° Hours *Note: Operation above 40°C and/or 50% RH will decrease half-life. 8 Ordering 8.
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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. FFSTN: Double film super-twisted nematic in reference to an LCD. The addition of two layers of film between the STN display and polarizer improves contrast. GPO: General purpose output, used to control peripheral devices from a display. GUI: Graphical user interface.