uLCD-28PTU
Datasheet
Revision 2.2
Copyright © 2023 4D Systems
Content may change at any time. Please refer to the resource centre for latest documentation.
Contents
1. Description
3
2. Features
4
3. Hardware Overview
5
4. Hardware Interface - Pins
8
4.1. Serial Ports - TTL Level
8
4.2. General Purpose I/O
9
4.3. System Pins
11
5. PmmC/Firmware Programming
13
6. Module Features
15
6.1. Display - 2.8" TFT Touch Screen
15
6.2. PICASO Processor
15
6.3. Audio
16
6.4. Lithium Batteries
16
6.5. SD/SDHC Memory Cards
17
6.6. FAT16
17
7. Display Precautions
18
8. Hardware Tools
19
8.1. Programming Cable/Adaptor
19
9. Programming Language
20
10. Workshop4 IDE
21
11. Starter Kit
22
12. Mechanical Details
23
13. Schematic Diagram
24
14. Specifications
25
15. Revision History
28
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uLCD-28PTU
Description
1. Description
The uLCD-28PTU module demonstrates class and finesse in the micro LCD range, featuring a 2.8''
240x320 screen resolution that is the ideal size for displaying detailed graphics for many interactive
touch applications.
Driving the display and peripherals is the PICASO processor, a very capable and powerful chip that
enables stand-alone functionality, programmed using the 4D Systems Workshop 4 IDE Software. The
Workshop IDE enables graphic solutions to be constructed rapidly and with ease due to its design
being solely for 4D graphics processors.
The module has an array of features including PWM for Sound, Touch Detection, micro-SD memory
storage, Lithium battery support, general purpose I/O, serial communications, an I2C interface and
multiple millisecond resolution timers, amongst many more features.
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uLCD-28PTU
Features
2. Features
• Low-cost 2.8" LCD-TFT display graphics user interface solution.
• 240 x 320 VGA resolution, RGB 65K true-to-life colours, TFT screen with Integrated 4-Wire
Resistive Touch Panel.
• Easy 5-pin interface to any host device: VCC, TX, RX, GND, RESET
• Powered by the 4D-Labs PICASO processor (also available as a separate OEM IC)
• 14KB of flash memory for user code storage and 14KB of SRAM for user variables, or 14KB shared
user code and program variables.
• 2 x Asynchronous hardware serial ports (COM0, COM1), TTL interface, with 300 to 600K baud.
• 1 x I2C interface (Master).
• 8 x 16-bit timers with 1-millisecond resolution.
• 13 x General Purpose I/O pins. Supports fast 8-bit parallel data transfer through Upper 8 bits.
• On-board micro-SD memory card adaptor for multimedia storage and data logging purposes.
HC memory card support is also available for cards larger than 4GB.
• DOS-compatible file access (FAT16 format) as well as low-level access to card memory.
• Lithium battery support, with built-in battery charger and automatic change-over.
• A dedicated PWM Audio pin driven by WAV files from a micro-SD card.
• On-board audio amplifier with a tiny 8Ω speaker for sound generation and WAV file playback.
• Built-in extensive 4DGL graphics and system library functions.
• Display full colour images, animations, icons and video clips.
• Supports all available Windows fonts.
• A 30-pin header for I/O expansion and future plug-in daughter boards.
• 4.0V to 5.5V range operation (single supply).
• Module dimensions: 52.00 x 83.69 x 15.9mm (including corner plates).
• Weighing ~ 42g.
• Display Viewing Area: 43.20 x 57.60mm
• 4 x corner plates with 2.7mm holes for mechanical mounting.
• RoHS Compliant.
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uLCD-28PTU
Hardware Overview
3. Hardware Overview
H2 Pinout (Programming Header)
Pin
Symbol
I/O
1
+5V
P
2
+5V
P
3
TX
O
4
TX
O
5
RX
I
6
RX
I
7
GND
P
8
GND
P
9
RES
I
10
RES
I
Description
Main Voltage Supply +ve input pin. Reverse polarity protected. The range is 4.0V to 5.5V,
nominal 5.0V.
Asynchronous Serial Transmit pin, TTL level. Connect this pin to the Receive (Rx) signal
of other serial devices. Used in conjunction with the RX pin for programming this micro
LCD. This pin is tolerant up to 5.0V levels.
Asynchronous Serial Receive pin, TTL level. Connect this pin to the Transmit (Tx) signal of
other serial devices. Used in conjunction with the TX pin for programming this micro
LCD. This pin is tolerant up to 5.0V levels.
Supply Ground
Master Reset signal. Internally pulled up to 3.3V via a 10K resistor. An active Low pulse
greater than 2 micro-seconds will reset the module. If the module needs to be reset
externally, only use open collector-type circuits. This pin is not driven low by any internal
conditions. The host should control this pin via one of its port pins using an open
collector/drain arrangement.
Note
I = Input, O = Output, P = Power
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uLCD-28PTU
Hardware Overview
H1 Pinout (Programming Header)
Pin
Symbol
I/O
Description
1
IO1
I/O
General Purpose Input Output 1 Pin (alternatively used as Frame Mark
pin when SB2 is closed)
2
SPK-
O
3
IO2
I/O
4
SPK+
O
5
IO3
I/O
6
SCL
O
7
IO4
I/O
General Purpose Input Output 4 Pin
8
SDA
I/O
I2C Bidirectional Data
9
IO5
I/O
General Purpose Input Output 5 Pin
10
N/C
-
Not connected
11
GND
P
Supply Ground
12
N/C
-
Not connected
13
GND
P
Supply Ground
14
+5V
P
Supply Input +ve, 4.0V to 5.5V, 5.0V Nominal
15
BUS7
I/O
IO Bus (BUS0..7) bit 7
16
AUDIO
I/O
Audio Input or Output, TTL Line level
17
BUS6
I/O
IO Bus (BUS0..7) bit 6
18
AUDENB
I
19
BUS5
I/O
20
RES
I
21
BUS4
I/O
22
3.3V OUT
P
23
BUS3
I/O
24
RX0
I
25
BUS2
I/O
26
TX0
O
4D Systems
Speaker Output -ve, for external Speaker
General Purpose Input Output 2 Pin (alternatively used as Battery
Status pin pin when SB3 is closed)
Speaker Output +ve, for external Speaker
General Purpose Input Output 3 Pin (alternatively used as Peripheral
Supply pin when SB1 is closed)
I2C Clock Output
Audio Amplified Enable, Active High (5V)
IO Bus (BUS0..7) bit 5
Master Reset, Active Low (GND) (Refer H2 Pinout)
IO Bus (BUS0..7) bit 4
3.3V Output, 20mA Max supply
IO Bus (BUS0..7) bit 3
Asynchronous serial port 0 receive pin. COM0 (same as the RX pin on
the H2 Programming Header)
IO Bus (BUS0..7) bit 2
Asynchronous serial port 0 transmit pin. COM0 (same as the TX pin on
the H2 Programming Header)
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uLCD-28PTU
Hardware Overview
Pin
Symbol
I/O
Description
27
BUS1
I/O
IO Bus (BUS0..7) bit 1
28
TX1
O
29
BUS0
I/O
30
RX1
I
Asynchronous serial port 1 transmit pin. COM1
IO Bus (BUS0..7) bit 0
Asynchronous serial port 1 receive pin. COM1
Note
I = Input, O = Output, P = Power
P1 Pinout (Lithium Battery Header)
Pin
Symbol
I/O
Description
1
+
P
Lithium Ion or Polymer 3.7V Battery +ve Terminal
2
+
P
Lithium Ion or Polymer 3.7V Battery +ve Terminal
3
N/C
-
Not connected
4
N/C
-
Not connected
5
-
P
Lithium Ion or Polymer 3.7V Battery -ve Terminal
6
-
P
Lithium Ion or Polymer 3.7V Battery -ve Terminal
Please refer to the Lithium Batteries section before using the Lithium Battery Header
Note
I = Input, O = Output, P = Power
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uLCD-28PTU
Hardware Interface - Pins
4. Hardware Interface - Pins
The uLCD-28PTU provides both a hardware and software interface. This section describes in detail
the hardware interface pins of the device.
4.1. Serial Ports - TTL Level
The uLCD-28PTU has two dedicated hardware Asynchronous Serial ports that can communicate
with external serial devices. These are referred to as the COM0 and the COM1 serial ports.
The primary features are:
• Full-Duplex 8-bit data transmission and reception.
• Data format: 8 bits, No Parity, 1 Stop bit.
• Independent Baud rates from 300 baud up to 600K baud.
• Single byte transmits and receives a fully buffered service. The buffered service feature runs in
the background capturing and buffering serial data without the user application having to
constantly poll any of the serial ports. This frees up the application to service other tasks.
A single-byte serial transmission consists of the start bit, 8 bits of data followed by the stop bit. The
start bit is always 0, while a stop bit is always 1. The LSB (Least Significant Bit, Bit 0) is sent out first
following the start bit. The figure below shows a single-byte transmission timing diagram.
COM0 is also the primary interface for 4DGL user program downloads and chip configuration PmmC
programming. Once the compiled 4DGL application program (EVE byte-code) is downloaded and
the user code starts executing, the serial port is then available to the user application. Refer to the
PmmC/Firmware Programming section for more details.
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uLCD-28PTU
General Purpose I/O
TX0 pin (Serial Transmit COM0):
Asynchronous Serial port COM0 transmit pin, TX0. Connect this pin to the external serial
device receive (Rx) signal. This pin is 5.0V tolerant.
RX0 pin (Serial Receive COM0):
Asynchronous Serial port COM0 receive pin, RX0. Connect this pin to an external serial
device transmit (Tx) signal. This pin is 5.0V tolerant.
TX1 pin (Serial Transmit COM1):
Asynchronous Serial port COM1 transmit pin, TX1. Connect this pin to the external serial
device receive (Rx) signal. This pin is 5.0V tolerant.
RX1 pin (Serial Receive COM1):
Asynchronous Serial port COM1 receive pin, RX1. Connect this pin to an external serial
device transmit (Tx) signal. This pin is 5.0V tolerant.
4.2. General Purpose I/O
There are 13 general purpose Input/Output (GPIO) pins available to the user. These are grouped as
IO1..IO5 (Note for IO1, IO2 and IO3 below) and BUS0..BUS7. Power-Up Reset default is all INPUTS.
The 5 I/O pins (IO1..IO5), provide flexibility for individual bit operations while the 8 pins (BUS0..BUS7),
known as GPIO BUS, serve collectively for byte-wise operations. The IO4 and IO5 also act as strobing
signals to control the GPIO Bus. GPIO Bus can be read or written by strobing a low pulse (50ns
duration or greater) the IO4/BUS_RD or IO5/BUS_WR for read or write respectively.
Please refer to the Picaso Internal Functions Manual for detailed information.
IO1-IO5 pins:
General purpose I/O pins. Each pin can be individually set for INPUT or an OUTPUT.
IO1-IO3 have also optional functionality when its dedicated Solder Jumper is closed. Please
read below for more information.
IO1 pin (Frame Mark pin):
The IO1 pin has 2 functions. It can be used as a GPIO pin (Default on HW >= 13.0 onward)
but can also be used to detect the start of a Frame (Default on HW < 13.0). When used as a
Frame Mark pin, simply solder its dedicated solder jumper SB2. When using IO1 for Frame
Mark read the status of IO1 as an Input.
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uLCD-28PTU
General Purpose I/O
IO2 pin (Lithium Battery Status pin):
The IO2 pin has 2 functions. It can be used as a GPIO pin (Default on HW >= 13.0) but can
also be used to tell when the Lithium battery has reached a low level (3.7V) and needs to be
charged (Default on HW < 13.0). When used as a Lithium Battery Status pin, simply solder
its dedicated solder jumper SB3. When using IO2 for Battery Status read the status of IO2
as an Input. (See the Lithium Batteries section for more information).
IO3 pin (Peripheral Supply pin):
The IO3 pin has 2 functions. It can be used as a GPIO pin (Default HW >= 13.0) but can also
be used as a Peripheral Supply pin (Default HW < 13.0) when its dedicated solder jumper
SB1 is closed.
IO3 set as a Peripheral Supply pin is controllable via the processor, or via the H2 Interface
pin driven by an external circuit. If IO3 is set as OUTPUT and driven HIGH the uSD card and
Display are enabled, and disabled when driven LO. Set as INPUT to use an external circuit to
drive this pin.
IO4/BUS_RD pin (GPIO IO4 or BUS_RD pin):
General Purpose IO4 pin. Also used for BUS_RD signal to read and latch the data into the
parallel GPIO BUS0..BUS7.
IO5/BUS_WR pin (GPIO IO5 or BUS_WR pin):
General Purpose IO5 pin. Also used for BUS_WR signal to write and latch the data to the
parallel GPIO BUS0..BUS7.
BUS0-BUS7 pins (GPIO 8-Bit Bus):
8-bit parallel General purpose I/O Bus.
Note
All GPIO pins are 5.0V tolerant.
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uLCD-28PTU
System Pins
4.3. System Pins
+5V (Module Voltage Input):
H1 pin 14, H2 pin 1 and 2:
Module supply voltage input pin. This pin must be connected to a regulated supply voltage
in the range of 4.0 Volts* to 5.5 Volts DC. The nominal operating voltage is 5.0 Volts.
3.3V Out (3.3V Regulated Output):
H1 pin 22:
External circuitry that requires a regulated 3.3V supply can be powered up via this pin. The
maximum available current is 150mA. Attempting to draw more can result in peripherals
such as the microSD card, not working correctly.
GND (Module Ground):
H1 pin 11/13, H2 pin 7 and 8:
Device ground pins. These pins must be connected to the ground.
RESET (Module Master Reset):
H1 pin 20, H2 pin 9 and 10:
Module Master Reset pin. An active low pulse of greater than 2μs will reset the module.
Internally pulled up to 3.3V via a 10K resistor. Only use open collector-type circuits to reset
the device if an external reset is required.
SPK-/SPK+ (External Speaker Outputs):
H1 pin 2/4 Respectively:
External Speaker Outputs, designed to drive an 8Ω speaker to a maximum of 1.2W. These
are connected in Parallel with the onboard speaker.
AUDENB (Audio Enable Output):
H1 pin 18:
Output dedicated to enabling or disabling an external amplifier if the onboard amplifier is
not desirable to use. Controlled by the PICASO processor. When AUDENB is low, the
onboard Amplifier is Enabled. When AUDENB is high, the onboard Amplifier is Disabled.
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uLCD-28PTU
System Pins
AUDIO (Audio Line Level Input/Output):
H1 pin 16:
Universal Input or Output specifically for Audio. This pin connects directly to the onboard
amplifier, but also with the filtered PWM output from the PICASO Processor. This pin can
be used to input a signal into the onboard amplifier to play audio from an external device
using the onboard amplifier, or as a line-level output to drive an external amplifier with
PICASO generated Audio. Note that AUDENB must be enabled (low) in PICASO for any
input signal to be heard.
+/- (Lithium Battery Terminals):
P1 pins 1/2(+ve), 5/6(-ve):
These are the terminals of the Lithium Battery connector. These are to be connected only to a
Lithium Ion or Polymer 3.7V Battery else the uLCD-24PTU may be damaged. See the Lithium
Batteries section.
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uLCD-28PTU
PmmC/Firmware Programming
5. PmmC/Firmware Programming
The PICASO processor used in the uLCD-28PTU module is a custom graphics processor. All
functionality including the high-level commands is built into the chip. This chip-level configuration is
available as a Firmware/PmmC (Personality-module-micro-Code) file.
A PmmC file contains all of the low-level micro-code information (analogy of that of a soft silicon)
which defines the characteristics and functionality of the device. The ability to program the device
with a PmmC file provides an extremely flexible method of customising as well as upgrading it with
future enhancements.
The Display Driver contains the initialisation and parameters associated with the particular display
that is to be connected to the PICASO processor.
The PmmC file and Display Driver file can only be programmed into the device via the COM0 serial
port with the aid of Workshop4, the 4D Systems IDE software.
Using a non-4D programming interface could damage your module, and void your Warranty.
PmmC Loader is a GUI interface designed to download PmmC's and Drivers to 4D Systems
Processors. It can automatically update existing PmmC's and Drivers present on a module, or
manually change or force download to a blank processor or module, overwriting anything written in
previously.
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uLCD-28PTU
PmmC/Firmware Programming
Program Loader is a GUI interface designed to download Applications to either Flash or RAM, useful
for testing or production loading, without the need for Workshop4 itself.
Please contact our Support Team for more information on what we can provide. Some solutions also
exist for external processor-based loading, if there is a requirement for that. This solution is available
under NDA.
Using a non-4D programming interface could damage your module, and void your Warranty.
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uLCD-28PTU
Module Features
6. Module Features
The uLCD-28PTU module is designed to accommodate most applications. Some of the main
features of the module are listed below.
6.1. Display - 2.8" TFT Touch Screen
The uLCD-28PTU module is equipped with a 2.8" TFT display. Details of the display are listed below:
• Screen Size: 2.8" diagonal
• Resolution: 240 x 320
• Integrated 4-Wire Resistive Touch Screen
• Screen Dimensions: 50.00 x 69.20 x 3.60mm
• Viewing Area: 43.20 x 57.60mm
• Pixel Pitch: 0.180 x 0.180mm
• Brightness: 150cd/m2
• Contrast Ratio: 250:1
• Viewing Angle Above Centre: 20 degrees
• Viewing Angle Below Centre: 30 degrees
• Viewing Angle Left of Centre: 40 degrees
• Viewing Angle Right of Centre: 40 degrees
• Viewing Direction: 6 O'clock
• 4 Parallel LEDs for Backlighting
Note
The Displays used are the highest-rated 'Grade A' Displays, which allow for 0-4 defective pixels. A defective
pixel could be solid Black (Dead), White, Red, Green or Blue.
6.2. PICASO Processor
The module is designed around the PICASO Graphics Controller from 4D-Labs.
The PICASO is a smart Controller and the interface to the TFT- LCD is almost plug-nplay.
All of the data and control signals are provided by the chip to interface directly with the display.
Powerful graphics, text, images, animation and countless more features are built right inside the
chip.
For more information read the Picaso Processor datasheet.
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uLCD-28PTU
Audio
6.3. Audio
Audio playback support in the PICASO Processor enables the uLCD-28PTU module to play audio
WAV files stored in the micro-SD memory card. PWM and an onboard audio amplifier with 8Ω
speaker ensure ample audio output capability. A simple instruction enables the user to play/pause/
stop audio files while continuing the execution of the user application code, such as display updates,
touch recognition, communications, etc. The audio system also allows real-time pitch change of
audio samples.
For a complete list of audio commands please refer to the Picaso 4DGL Internal Functions.
Note
The onboard speaker is a small device designed to project into an audio cavity. It is not very loud by itself. To
enable louder audio, it is recommended to use a larger external 8Ω speaker. See the System Pins section for
more information.
6.4. Lithium Batteries
The uLCD-28PTU module includes a battery charging circuit suitable for Lithium Ion (LiIon) and
Lithium Polymer (LiPo) batteries, which is designed to work only with 3.7V batteries. If anything
other than a LiIon or LiPo 3.7V battery is connected the module could be damaged. Features current
sensing and reverse discharge protection using an onboard Lithium charge management controller.
When the Lithium battery is connected and an external source (4.5V minimum) is connected to
either of the +5V pins, the Lithium battery will be charged automatically. If the 5V source is
disconnected, the Lithium battery will be switched in the circuit and continue to power the module
automatically.
Charge voltage = 4.2V, Charge current = ~210mA
When running from the Lithium battery, when the battery level drops down to ~3.7V, the Status
input (connected to IO2) into the Picaso will be triggered indicating the battery is discharged. The
display should then be connected to an external 5V source for charging. When the battery is at this
cut-off voltage, μSD card read and write operations should be avoided, as they may fail due to low
voltage. It is up to the User to handle the operation of the display module when using a Lithium
Battery.
Note
There is a large range of Lithium batteries available on the market. Some include safety circuits built in, while
others do not. Lithium batteries can explode if short-circuited, overcharged, if they get too hot, and can leak if
they sit fully discharged for a prolonged period.
4D Systems recommends whenever Lithium batteries are used that caution and due diligence
should be exercised to ensure the safety of the user and nearby people. While the chances of
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uLCD-28PTU
SD/SDHC Memory Cards
explosion or leakage may be minimal, 4D Systems recommends safe practices at all times when
dealing with these batteries.
If Lithium Batteries are powering the module, it is highly recommended to periodically monitor the
STAT pin. If the module is put to sleep, periodically wake the module to check the STAT pin.
6.5. SD/SDHC Memory Cards
The module supports micro-SD memory cards via the onboard micro-SD connector.
The memory card is used for all multimedia file retrieval such as images, animations
and movie clips. The memory card can also be used as general-purpose storage for
data logging applications. Support is available for off-the-shelf micro-SD and highcapacity HC memory cards (4GB and above).
Note
A microSD card capable of SPI is a requirement for all 4D Systems' display modules powered by Goldelox,
Picaso or Diablo16 Processors. If a non-SPI compatible card is used, it will simply fail to mount, or may cause
intermittent issues resulting in lockups and crashing of the application. Please refer to the 4D Systems
website for microSD cards offered by 4D Systems.
6.6. FAT16
The uLCD-28PTU uses off-the-shelf standard SDHC/SD/micro-SD memory cards with up to 4GB
capacity usable with FAT16 formatting. For any FAT file-related operations, before the memory card
can be used it must first be formatted with the FAT16 option. The formatting of the card can be done
on any PC system with a card reader. Select the appropriate drive and choose the FAT16 (or just FAT
in some systems) option when formatting. The card is now ready to be used in the PICASO-based
application.
The uLCD-28PTU also supports high-capacity HC memory cards (4GB and above). The available
capacity of SD-HC cards varies according to the way the card is partitioned and the commands used
to access it.
The FAT partition is always first (if it exists) and can be up to the maximum size permitted by FAT16.
Windows 7 will format FAT16 up to 4GB. Windows XP will format FAT16 up to 2GB and the Windows
XP command prompt will format FAT16 up to 4GB.
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uLCD-28PTU
Display Precautions
7. Display Precautions
• Avoid having to display the same image/object on the screen for lengthy periods. This will cause
a burn-in which is a common problem with all types of display technologies. Blank the screen
after a while or dim it very low by adjusting the contrast. Better still; implement a screen saver
feature.
• Moisture and water can damage the display. Moisture on the surface of a powered display will
cause the electrodes to corrode. Wipe off any moisture gently or let the display dry before usage.
• Dirt from fingerprint oil and fat can easily stain the surface of the display. Gently wipe off any
stains with a soft lint-free cloth.
• The performance of the display will degrade under high temperatures and humidity. Avoid such
conditions when storing.
• Do not tamper with the display flex cable that is connected to the control board. This may affect
the connection between the display and the driving circuitry and cause failure.
• Displays are susceptible to mechanical shock and any force exerted on the module may result in
deformed zebra stripes, a cracked display cell and a broken backlight
• Always use the mounting holes on the module's corner plates to mount the display.
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uLCD-28PTU
Hardware Tools
8. Hardware Tools
The following hardware tools are required for full control of the uLCD-28PTU module.
8.1. Programming Cable/Adaptor
The 4D Programming Cable and uUSB-PA5/uUSB-PA5-II Programming Adaptors are essential
hardware tools to program, customise and test the PICASO Processor.
Either the 4D Programming Cable or the uUSB-PA5 Programming Adaptor can be used.
The 4D programming interfaces are used to program a new Firmware/PmmC, Display Driver and for
downloading compiled 4DGL code into the processor. They even serve as an interface for
communicating serial data to the PC.
4D Programming Cable
uUSB-PA5-II Programming Adaptor
Note
In addition to these modules, the gen4-PA and 4D-UPA can also be used.
Using a non-4D programming interface could damage your processor, and void your Warranty.
These programming interfaces are available from the 4D Systems website.
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uLCD-28PTU
Programming Language
9. Programming Language
The uLCD-28PTU uses the PICASO processor, which belongs to a family of processors powered by a
highly optimised softcore virtual engine, EVE (Extensible Virtual Engine).
EVE is a proprietary, high-performance virtual machine with an extensive byte-code instruction set
optimised to execute compiled 4DGL programs. 4DGL (4D Graphics Language) was specifically
developed from ground up for the EVE engine core. It is a high-level language that is easy to learn
and simple to understand yet powerful enough to tackle many embedded graphics applications.
4DGL is a graphics-oriented language allowing rapid application development, and the syntax
structure was designed using elements of popular languages such as C, Basic, Pascal and others.
Programmers familiar with these languages will feel right at home with 4DGL. It includes many
familiar instructions such as IF..ELSE..ENDIF, WHILE..WEND, REPEAT..UNTIL, GOSUB..ENDSUB, GOTO,
PRINT as well as some specialised instructions SERIN, SEROUT, GFX_LINE, GFX_CIRCLE and many more.
For detailed information about the 4DGL language, please refer to the following documents:
• 4DGL Programmers Reference Manual
• Goldelox Internal Functions Manual
To assist with the development of 4DGL applications, the Workshop4 IDE combines a full-featured
editor, a compiler, a linker and a downloader into a single PC-based application. It's all you need to
code, test and run your applications.
4DGL is available to be written in two of the four environments offered by the Workshop4 IDE,
Designer and ViSi. The other two environments, Serial and ViSi-Genie do not directly use 4DGL by the
User (Except in Workshop4 Pro, for ViSi-Genie), however, it is present in the background. Serial is an
application that runs, and that is written in 4DGL. ViSi-Genie automatically generates 4DGL itself
based on what is configured in the GUI.
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uLCD-28PTU
Workshop4 IDE
10. Workshop4 IDE
Workshop 4 is a comprehensive software IDE that provides an integrated software development
platform for all of the 4D family of processors and modules. The IDE combines the Editor, Compiler,
Linker and Down-Loader to develop complete 4DGL application code. All user application code is
developed within the Workshop 4 IDE.
The Workshop 4 IDE supports multiple development environments for the user, to cater to different
user requirements and skill levels.
• The Designer environment enables the user to write 4DGL code in its natural form to program
the uLCD-35DT Module.
• A visual programming experience, suitably called ViSi, enables drag-and-drop type placement of
objects to assist with 4DGL code generation and allows the user to visualise how the display will
look while being developed.
• An advanced environment called ViSi-Genie doesn't require any 4DGL coding at all, it is all done
automatically for you. Simply lay the display out with the objects you want, set the events to drive
them and the code is written for you automatically. ViSi-Genie provides the latest rapid
development experience from 4D Systems.
• A Serial environment is also provided to transform the display module into a slave serial module,
allowing the user to control the display from any host microcontroller or device with a serial port.
For more information regarding these environments, refer to the Workshop4 manuals.
The Workshop4 IDE is available from the 4D Systems website.
4D Systems
DATASHEET
Page 21 of 28
uLCD-28PTU
Starter Kit
11. Starter Kit
4D Systems highly recommends all first-time buyers of 4D Systems' displays, to purchase the Starter
Kit when purchasing their first 4D Systems display solution.
The Starter Kit provides all the hardware that is required to get the user up and running.
Not all development environments and features will be needed by every user, however, purchasing
the display solution in a Starter Kit, ensures that if you want to take full advantage of the 4D Systems
display solution and try out each of the 4D Workshop4 Environments, upgrade PmmC/firmware, you
can.
The Designer environment can use every feature of the display, however, depending on the user
requirements, a micro-SD (uSD) card may not be required. The uSD card is used when displaying
images/video/sound, along with data logging to uSD, and a programming cable is required for
downloading compiled code and PmmC/Firmware updates.
The ViSi environment is the same as Designer in terms of feature utilisation, but is image based so
requires a uSD card, along with a programming cable.
The ViSi-Genie environment is also image-based, and therefore requires a uSD card and
programming cable also.
The Serial environment does not require either a uSD or Programming cable to be used, however,
can use both depending on the user's requirements. The uSD card can be used for such things as
storage of multimedia files and data logging, and the Programming cable for PmmC/Firmware
updates, or changing to one of the other three programming environments.
The Starter Kit includes:
• uLCD-28PTU Display Module
• 4GB MicroSD Card
• uUSB-PA5-II Programming Adaptor
• 150mm 5-way Female-Female jumper cable, for quick connection to another device or
breadboard
• 5-way Male-Male adaptor (for converting the Female-Female cable to be Male-Female)
Simply select the Starter Kit option when purchasing the chosen display module on the 4D Systems
shopping cart, or from your local distributor.
4D Systems
DATASHEET
Page 22 of 28
uLCD-28PTU
Mechanical Details
12. Mechanical Details
4D Systems
DATASHEET
Page 23 of 28
uLCD-28PTU
Schematic Diagram
13. Schematic Diagram
4D Systems
DATASHEET
Page 24 of 28
uLCD-28PTU
Specifications
14. Specifications
Absolute Maximum Ratings
Operating ambient temperature
-20°C to +70°C
Storage temperature
-30°C to +80°C
Voltage on any digital input pin with respect to GND
-0.3V to 6.0V
Voltage on SWITCH pin with respect to GND
-0.3V to 6.0V
Voltage on VCC with respect to GND
-0.3V to 6.0V
Note
Stresses above those listed here may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at those or any other conditions above those indicated in the
recommended operation listings of this specification is not implied. Exposure to maximum rating conditions
for extended periods may affect device reliability.
Recommended Operating Conditions
Parameter
Conditions
Supply Voltage
(VCC)
Processor voltage
(VP)
Operating
Temperature
Min
Typ
Max
Units
4.0
5.0
5.5
V
--
3.3
--
V
-10
--
+60
°C
0
--
0.2VP
V
Input Low Voltage
(VIL)
all pins
Input High Voltage
(VIH)
non 5V tolerant pins
0.8VP
--
3.3
V
Input High Voltage
(VIH)
All GPIO pins, RX0 and
TX0 pins
0.8VP
--
5.5
V
Reset Pulse
External Open Collector
2.0
--
--
µs
Operational Delay
Power-Up or External
Reset
500
--
3000
ms
4D Systems
DATASHEET
Page 25 of 28
uLCD-28PTU
Specifications
Global Characteristics Based on Operating Conditions
Parameter
Conditions
Min
Typ
Max
Units
Supply Current
(ICC)
VCC = 5.0V, heavily depends on screen
usage conditions, sleep mode
10
120
200
mA
Output Low
Voltage (VOL)
VCC = 5.0V, IOL = 3.4mA
--
--
0.4
V
Output High
Voltage (VOH)
VCC = 5.0V, IOL = -2.0mA
2.8
--
--
V
Capacitive
Loading
All pins
--
--
50
pF
Flash Memory
Endurance
PICASO PmmC Programming
--
10000
--
E/W
TOUCH SCREEN CHARACTERISTICS
Parameter
Conditions
Linearity
Min
Typ
Max
Units
--
--
10
20
Viewing Angle
Vertical below Centre
35
Viewing Angle
Horizontal Left of Centre
40
Viewing Angle
Horizontal Right of Centre
40
4D Systems
DATASHEET
Degrees
Page 27 of 28
uLCD-28PTU
Revision History
Order Information
Order Code: uLCD-28PTU
Package: 105mm x 65mm x 30mm
Packaging: Module sealed in antistatic foam padded 4D Systems Box
15. Revision History
Hardware Revision
Revision
Number
Date
6
12/06/2012
Initial release of PTU revision
8
10/07/2012
R29 / R32 / R6 /R44 have changed values
11.1
19/02/2013
- Resistor R46 has been implemented to enable GPIO usage for IO3 if removed
- Resistor R22 is no longer mounted
- Resistors R8, R28, R29, R32, R44 have changed values
11.2
26/02/2013
R18 specified as 1M2, must be Do Not Mount (DNM) and not inserted during SMT
12.1
23/04/2014
Battery charging circuit has been improved
29/04/2015
- Resistors R7, R28, R46 have been removed and replaced with solder jumpers (SB1 / SB2 /
SB3)
- Both sides of the H2 Programming Header are now connected to its dedicated signals
- Audio Amplifier circuitry has been improved to remove background noise
- Power circuit has been changed: U2 & U5 are different components now and L3 and L4
have been added. 30Pin Header 3.3V output can deliver 150mA instead of 20mA. The R4
current limiting resistor has been removed. SD Card circuit has been changed: R18 is now
a 10k Resistor.
13.0
Description
Datasheet Revision
Revision Number
Date
1.9
04/05/2017
Initial Public Release
2.0
19/10/2017
Updated Specifications Section
2.1
03/04/2019
Cosmetic Changes to micro LCD Datasheet range
2.2
13/01/2023
Modified datasheet for web-based documentation
4D Systems
Description
DATASHEET
Page 28 of 28