LK202-25/VK202-25 Including LK202-25-USB a nd V K202 -25-USB Technical Manual Revision 4.1 PCB Revision: 3.0 or Higher (Standard Model), 1.0 or Higher (USB Model) Firmware Revision: 5.
Revision History Revision 4.1 4.
Contents 1 Introduction ............................................................................................................................................... 1 2 Quick Connect Guide.................................................................................................................................. 2 2.1 Available Headers ............................................................................................................................... 2 2.2 Standard Module ................
5.3 Communication ................................................................................................................................. 14 5.4 Manual Override ............................................................................................................................... 14 6 Commands ............................................................................................................................................... 15 6.1 Communication ..................................
1 Introduction Figure 1: LK202-25 Display Figure 2: VK202-25 Display The LK202-25/VK202-25 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, a USB communication model allow the LK202-25/VK202-25 to be connected to a wide variety of host controllers. Communication speeds of up to 115.
2 Quick Connect Guide 2.
2.2 Standard Module The standard version of the LK202-25/VK202-25 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 LK202-25/VK202-25. 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.
2.3 USB Module The LK202-25/VK202-25-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 mini B style USB connector as outlined in the USB Connections section. Recommended Parts The External Mini USB cable is recommended for the LK202-25/VK202-25USB display. It will connect to the miniB 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 LK202-25/VK20225 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 8: 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 Pin 1 2 3 4 Function Vcc Rx (SCL) Tx (SDA) Gnd Figure 9: Communication/Power Header The Communication/Power Header provides a standard connector for interfacing to the LK20225/VK202-25. 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 LK202-25/VK202-25 allows all voltage models to use the power through DB-9 option, see the Voltage Specifications for power requirements.
4.2 USB Model Mini USB Connector Table 6: Mini USB Pinout Figure 12: Mini USB Connector Pin 1 2 3 5 Function Vcc DD+ Gnd The LK202-25/VK202-25-USB comes with a familiar Mini USB Connector to fulfill both communication and power needs. The standard MiniB style header can be connected to any other USB style using the appropriate 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.
4.3 Common Features General Purpose Outputs Table 8: GPO Pinout Figure 14: 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 LK202-25/VK202-25 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 10: Keypad Pinout Figure 16: 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 LK202-25/VK202-25 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 LK202-25/VK202-25 to function correctly, it must be supplied with the appropriate power. If the screen is not illuminated, power may not be applied correctly. Try 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. v5.6 Table 12: 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. v5.6 2.2 Change the Start Up Screen Dec 254 64 Characters v5.6 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. v5.6 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. v5.6 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. v5.6 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. v5.6 2.
6.3 Special Characters 3.1 Create a Custom Character Dec 254 78 ID Data v5.6 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 v5.6 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 v5.6 Hex FE 6D ASCII ■m Loads the medium number custom character bank into memory.
3.10 Initialize Wide Vertical Bar Dec 254 118 v5.6 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. 3.11 Place Vertical Bar Dec 254 61 Column Length v5.6 Hex FE 3D Column Length ASCII ■ = Column Length Places a vertical bar graph on the screen extending from the first row of the column specified. The bar extends upwards to the length indicated.
6.5 Dallas One-Wire 5.1 Search for a One-Wire Device Dec 254 200 2 v5.6 Hex FE C8 02 ■ ╚ SOT ASCII Sends a search query to each of the up to 32 devices on the one wire bus. Any connected device will respond with an identification packet. Response Bytes [14] Dallas One-Wire identification packet as shown below.
6.6 Keypad 6.1 Auto Transmit Key Presses On Dec 254 65 Hex FE 41 ASCII ■A Key presses are automatically sent to the host when received by the display. Default is Auto Transmit on. v5.6 6.2 Auto Transmit Key Presses Off Dec 254 79 v5.6 Hex FE 4F ASCII ■O Key presses are held in the 10 key buffer to be polled by the host using the Poll Key Press command. Use this mode for I2C transactions. Default is Auto Transmit on. 6.3 Poll Key Press Dec 254 38 v5.
6.7 Auto Repeat Mode Off Dec 254 96 Hex FE 60 ■` ASCII Turns auto repeat mode off. Default is on (typematic). v5.6 6.8 Assign Keypad Codes Dec 254 213 Key Down Key Up v5.6 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.
7.3 Set Brightness* Dec 254 153 Brightness Hex FE 99 Brightness ASCII ■ Ö Brightness Immediately sets the backlight brightness. If an inverse display color is used this represents the text colour intensity instead. Default is 255. Brightness Byte Brightness level from 0(Dim) to 255(Bright). v5.6 7.4 Set and Save Brightness* Dec 254 152 Brightness v5.6 Hex FE 98 Brightness ASCII ■ ÿ Brightness Immediately sets and saves the backlight brightness.
6.8 Data Security 8.1 Set Remember Dec 254 147 Switch v5.6 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 v5.6 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 v5.6 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 25: 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 29: Display Functions Command Summary Name Backlight On Backlight Off Set Brightness* Set and Save Brightness* Set Contrast* Set and Save Contrast* Set VFD Brightness** Set and Save VFD Brightness** Dec 66 70 153 152 80 145 89 145 Hex 42 46 99 98 50 91 59 91 ASCII B F Ö ÿ P æ Y æ Parameters Byte None Byte Byte Byte Byte Byte Byte Response None None None None None None None None Remembered Remember On Remember On Remember On Always Remember On Always Remember On Always Note*: LCD Model specific
7.
Figure 18: VFD Model Japanese Character Set 31
7.3 Block Diagram Figure 19: Functional Diagram 7.4 Environmental Specifications Table 32: Environmental Limits Operating Temperature Storage Temperature Operating Relative Humidity Thermal Shock LCD Standard LCD Extended (-E) VFD Standard VFD Extended (-E) 0°C to +50°C -20°C to +70°C -20°C to +70°C -40°C to +85°C -10°C to +60°C -30°C to +80°C -40°C to +85°C -50°C to +85°C Maximum 90% non-condensing Maximum 80% non-condensing Maximum 10°C /min 7.
7.
Figure 22: LK202-25-USB Dimensional Drawing Figure 23: VK202-25-USB Dimensional Drawing 34
7.7 Optical Characteristics Table 36: Display Optics Module Size Viewing Area Active Area Character Size Character Pitch Pixel Size Pixel Pitch Viewing Direction Viewing Angle Contrast Ratio VFD Brightness Backlight Half-Life LCD Model VFD Model 116.00 x 37.00 x 29.0 63.0 x 18.6 96.0 x 24.0 73.5 x 11.5 70.8 x 11.6 3.20 x 5.55 2.40 x 4.70 3.70 x 5.95 3.60 x 6.10 0.55 x 0.60 0.40 x 0.50 0.60 x 0.65 0.50 x 0.
8.3 Accessories Power Table 39: Power Accessories PCS Standard Power Cable Communication Table 40: Communication Accessories CSS1FT 1 ft. Serial Cable CSS4FT 4 ft.
Peripherals Table 41: Peripheral Accessories KPP4x4 16 Button Keypad KPP20A-XX* 7 Button Keypad Overlay Temperature Probe Dallas One-Wire Temperature Probe Mounting Table 42: Mounting Accessories B2041-XX** Mounting Bracket with Coloured Overlay B204A-XX* Mounting Bracket with Keyed Overlay MK2041-XX** Coloured Overlay with Drill Guide *Note: Keyed overlays are available in Black (-BK), Silver (-SK), Red (-DR), and Beige(no part extension) Vinyl.
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.
