MATRIX ORBITAL GTT35A Full Colour TFT Display User Manual
- June 3, 2024
- MATRIX ORBITAL
Table of Contents
MATRIX ORBITAL GTT35A Full Colour TFT Display
Introduction
The Matrix Orbital GTT35A is a full-colour TFT display with an integrated touch screen, crafted to become a crisp, controllable canvas for creativity. Utilizing an extended version of our widely used command library and industry- standard communication protocols, the customizable GTT35A series contains an intelligent display that will quickly become the gorgeous face of your application.
Features
- In addition to a beautiful full-colour TFT screen, seamless incorporation of a touch panel provides sleek user input while a small piezo speaker and vibratory motor can offer audio and tactile feedback for a completely interactive experience. Storage of fonts and bitmaps within the swappable onboard SD memory card allows for a co-ordinated appearance in any design.
- The elegant simplicity of the familiar Matrix Orbital command structure now provides updates to the user and optional flow control for full two-way communication. Also new are animations, full-colour graphs, automated display initialization, and field upgradeability.
Available flow controlled RS232 and TTL interfaces, as well as an I2 C protocol provide versatile communication schemes, while USB and RS422 versions ensure that any controller can have a beautiful user interface. Scorching fast communication speeds, up to 256kbps in serial modes and 400kHz in I2C, ensure important information is relayed on time.
Ordering
The innovative GTT35A, with all of the features mentioned above, is available in various voltage and communication options to provide a sleek touch of creativity to any project.
Ordering Part Numbering Scheme
Options
Note : All options may not be available, please consult www.matrixorbital.com for a list of purchasable products.
Recommended Parts
- The most common cable choice for the any GTT display, the Extended Communication/ Power Cable offers a simple connection to the unit with familiar interfaces. A DB9 and floppy power header provide all necessary input to communicate to and power your display.
- For a more flexible interface to the GTT, especially with the I2 C protocol, a Breadboard Cable may be used. This provides a simple four wire connection that is popular among developers for its ease of use in a breadboard environment.
- The External Mini-B USB Cable is recommended for USB communication. It will connect to the Mini-B style header on the unit and provide a connection to a regular A style USB connector, commonly found on a PC
- The standard power cable can be used to apply power to the GTT, either in conjunction with the ESCCPC5V cable, or via a direct connection to the Alternate Power Header. It connects to a standard PC power supply.
- An External Mini-B USB Cable may also be used to access data within the onboard SD card when removing the card itself is not possible. This connection also provides power to the GTT and can be more convenient than moving the SD card from one location to another.
Hardware
Available Headers
Extended Serial Communication/Power Header
The communication/power header provides an interface for the two most common
GTT35A protocols: RS232 and TTL. With the ability to connect to a PC serial
port or microcontroller and optional hardware flow control, this is the most
versatile header available on the GTT35A
Voltage is applied through pins one and four of the header, please reference electrical specifications before applying power. Pins two and three are reserved for serial transmission using either RS-232/TTL levels, depending on what model has been ordered. Finally, pins five and six are used for optional hardware flow control. The Serial Molex 22-04-1061 style header used can be mated to a number of connectors, including a 22-01-1062.
Mini-B USB Communication Connector
USB protocol offers an easy connection to any host computer. The simple and
widely available protocol can be accessed using the familiar Mini-B USB
connector to fulfill both communication and power needs.
The USB model can be connected to virtually any USB host using the appropriate cable, and additional power may be supplied through the alternate power header if necessary. Most commonly used with a PC, this connection creates a virtual com port that offers a simple power solution with a familiar communication scheme.
Alternate Power Connector
The Alternate Power Connector provides the ability to power the GTT35A using
an alternate cable*. This feature can supply additional power to the GTT that
your USB connection alone cannot provide, especially when peripherals such as
the piezo buzzer, motor and GPOs are used.
The standard Tyco 171825-4 style header is particularly useful for connecting to an unmodified floppy power cable, a 171822-4 for example, from a PC power supply for a simple bench power solution.
Note : Do not power the GTT35A using both USB and Alternate Power
connections. When using the Alternate
Power connector move the 0 ohm resistor at R37 to R15. If you have any
questions, please Contact a friendly Matrix Orbital support representative.
Note : When using a –VPT model, it may be desirable to input power to the GTT using the floppy power cable 12V connection. Please Contact a friendly Matrix Orbital support representative for modification details.
Alternate USB Communication Header
Some advanced applications may prefer the straight four pin connection offered
through the optional
Alternate USB Header. The Alternate USB Header may be added to the USB model
for an added charge as part of a custom order. Please use the Contact section
to reach Sales for additional details.
Drivers
The latest drivers are available for download in a zipped file format at www.matrixorbital.ca/drivers. To install or update the drivers installed on your PC, locate the GTT35A in your device manager, right click its’ icon, select Update Driver Software, and manually point to the unzipped driver file.
I2C Communication/Power Header
A dedicated I2C header is available on all GTT35A models and provides the most
basic protocol connection to the unit.
Voltage is applied through pins one and four of the header, please reference the electrical specifications before applying power. Pins two and three are reserved for I 2 C clock and data signals respectively, both of which should be pulled up to five volts using a resistance between one and ten kilohms. The Tyco 640456-4-LF style header used can be mated to a number of connectors, including Molex 22-01-3047.
RS422 Header
RS422 communication provides an industrial alternative to the standard RS232
communication protocol. Rather than single receive and transmit lines, the
RS422 model uses a differential pair for each receive and transmit signals to
reduce degradation and increase transmission lengths
The six pin RS422 Header offers a power and ground connections at either end, and two differential pair communication lines in the middle. Regular and inverted lines, labelled A/B and Z/Y, are provided for receive and transmit signals. The standard Tyco 282834-6 style header populated is best mated to a sized 16 to 30 on the American Wire Gauge connections that are secured via the header screws.
Mass Storage Mini-B USB Header
The GTT35A comes with a secondary Mini-B USB connector to access the SD memory
card as a mass storage device for easier access to the files contained on the
card.
The mass storage jumper must be placed to use this function, please refer to
the Mass Storage Mode section for further information.
Alternate USB Mass Storage Header
- Some advanced applications may prefer the straight four pin connection offered through the optional
- Alternate Mass Storage Header. The Alternate Mass Storage Header may be added to the GTT35A as part of a custom order. Please use the Contact section to reach Sales for additional details.
Mass Storage Mode
- By placing a jumper on pins 6 and 7 of the keypad header, the unit will appear to any PC as a mass storage device when powered, giving you access to the contents of the SD memory card directly.
- When connected to the GTT Designer Tool, users will be able to place their GTT display in Mass Storage
- Mode using a software switch found in Designer Tools. The software switch allows users to switch between Mass Storage, and normal operating modes without having to manually reboot and reposition their jumpers.
- Please note, the speed of data transfers in mass storage mode is limited, and is only intended to be used in situations where an external SD memory card reader is not available.
SD Memory Card
- The SD Memory Card is used to store all user fonts, bitmaps, 9-slices, animations and start-up settings.
- The start-up settings are stored in a binary file called AUTOEXEC. This file contains a simple stream of characters stored just as they would be if they were sent to the display at runtime, this will store all the commands to change the initial settings for your application. Start-up settings are stored in this location alone; therefore, simply removing the AUTOEXEC file will restore the display to factory defaults.
- Please refer to the Protocol Manual at http://www.matrixorbital.ca/manuals/GTT-Series/ for a complete list of available commands executable not only at start up but runtime as well.
General Purpose Outputs
A unique feature of the GTT35A is the ability to control relays* and other external devices using either one of six General Purpose Output
Each can source up to 15mA of current at five volts when on, or sink 15mA at zero volts when off. The two row, fourteen pin header can be interfaced to a number of female connectors to provide control to any peripheral devices required.
Keypad Header
- To facilitate user input, the GTT35A provides a Keypad Connector which allows a matrix style keypad ofup 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. When a key press is generated, a character specific to that key press is automatically sent on the Tx communication line. If the display module is running in I²C mode, the key press will remain in the buffer until it is accessed using the display read address.
The character that is associated with each key press may be altered using the “Assign Key Codes” command. The straight twelve pin header of the Keypad Interface Connector will interface to a variety of different devices including the Matrix Orbital KPP4x4 keypad.
Note : If connecting a relay, be sure that it is fully clamped using a
diode and capacitor in order to absorb any electro-motive force (EMF) which
will be generated.
Note : The Ground / +5V pin is toggled by the jumper to the top right of
the keypad connector. Jump pads 1 & 2 for +5V or 2 & 3 for GND.
Troubleshooting
Power
To function correctly, the GTT35A 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 the tips below.
- GTT devices have specific power requirements. Ensure the correct voltage and sufficient current are available to your device by consulting the Power Consumption table.
- Check the power cable which you are using for continuity. If you don’t have an ohm meter, try using a different power cable, if this does not help try a different power supply.
- Check the power connector in use on your display. If the connector has become loose or you are unable to resolve the issue, please use the Contact section to reach a friendly Matrix Orbital support representative.
Display
If your display is powered successfully with an AUTOEXEC file present, the Matrix Orbital logo or user specified screen should display briefly on start up. If this is not the case, check out these tips.
- If any start-up issues are encountered, it is recommended that you remove the AUTOEXEC file from the SD card to allow the unit to start with factory defaults.
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.
In USB protocol, ensure that a connection is made to the header labelled USB, not Mass Storage and check that a mode selection jumper is not placed on keypad pins 6 and 7.
In serial protocol, ensure that the host system and display module are both communicating on the same baud rate. The default baud rate for the display module is 115,200 bps.
Match Rx from the display to the transmit pin from your host and the Tx pin to receive.
If you are communicating to the display via I²C* please ensure that the data is being sent to the correct address. The default slave address is decimal 80 (0x50 hex). In I2
C mode, connect SDA to the data line of your controller and SCL to the clock output.
Factory Defaults
If the settings of your display become altered in a way that dramatically impacts usability, the default settings can be restored simply by removing the AUTOEXEC file in the memory card’s root directory. This will remove the start screen and reset the baud rate to 115,200. If the Matrix Orbital start screen is desired, default files are available at www.matrixorbital.ca/manuals/GTT_Series/GTT_Example_Files.
Note : I²C communication will always require pull up resistors on SCL and SDA of one to ten kilohms.
Appendix
Dimensional Drawing
Power Consumption
Environmental
Touch Specifications
Optical Characteristics
ESD Performance
Electrical Characteristics
Communication Characteristics
Defect Criteria
- Display Specifications
- Appearance Specifications
Note : Defects must occur in Active Area
Definitions
- 9-Slice: Graphic format used to scale bitmaps, usually rectangular, without distorting their geometry.
- Nine regions define the object center, four corners, and four sides for accurate up or down scaling.
- 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.
- GUI: Graphical user interface.
- Hexadecimal: A base 16 number system utilizing symbols 0 through F to represent the values 0-15.
- C: Inter-integrated circuit protocol uses clock and data lines to communicate short distances at slow speeds from a master to up to 128 addressable slave devices. A display is a slave device.
- LSB: Least significant bit or byte in a transmission, the rightmost when read.
- MSB: Most significant bit or byte in a transmission, the leftmost when read.
- RS232: Recommended standard 232, a common serial protocol. Logic levels can be as high as +/-30V, a high level is negative, a low is positive.
- RS422: Recommended standard 422, a more robust differential pair serial protocol.
- SDA: Serial data line used to transfer data in I2
- C protocol. This open drain line should be pulled high through a resistor. Nominal values are between 1K and 10K Ω.
- SCL: Serial clock line used to designate data bits in I2
- C protocol. This open drain line should be pulled high through a resistor. Nominal values are between 1K and 10K Ω.
- TTL: Transistor-transistor logic applied to serial protocol. Low level is 0V while high logic is 5V.
- USB: Universal Serial Bus protocol widely used in PC
References
- Matrixorbital Support Site - Home
- Matrixorbital Support Site - Drivers - Drivers
- Manuals
- Gtt Series Device Database
- Matrix Orbital Display Solution Provider