4D Systems uLCD-32WPTU with BoosterPack for Stellaris
This 3.2" Color LCD with Touch and SD-Card BoosterPack for Stellaris from 4D Systems features a 3.2" 400 x 240 pixels screen with 256K colours, touch, speaker and micro-SD card slot.
It comes with a BoosterPack for the Stellaris LaunchPad.
The pins of the two connectors on the BoosterPack —one for the screen and another for the programming cables— aren't labelled, not even the ground, making the connections adventurous.
I had to test the +5V and ground pins individually to find the right connection.
Unfortunately with Energia, the BoosterPack relies on the PB_0 / PB_1 or 3 / 4 pins for Serial1, whilst the correct pins are PC_4 / PC_5 or 37 / 36 pins on the Stellaris LaunchPad.
The pins map is available at 4D Systems BoosterPack Adaptor.
However, I managed to connect it successfully using the PC_4 / PC_5 or 37 / 36 pins and a logic level converter.
I recommend placing a logic level converter --pictured right— for the serial RX/TX lines to obtain a better signal at high speed.
The Stellaris LaunchPad operates at 3.3V, but the screen requires 5V and 150 mA in normal usage. Power consumption can go even higher if the speaker is used, typically ~220 mA.
The major benefit is that only two pins, serial RX and TX, are required for managing all the components, including LCD, touch, speaker and SD-card.
The screen also includes the fonts, but not the extended ASCII characters required by European languages —as àéêëèùñæœ...
The module uses a proprietary GCU, called Picaso, to manage all the components. It is driven by a set of serial commands, called SPE2.
The screen module and the BoosterPack are carefully manufactured and very clean.
As usual, 4D Systems provides excellent documentation for the screen and for the serial commands, as well as many application notes.
The screen offers different modes:
On the right, the splash screen shows different releases:
Both can be updated.
Library for Serial Mode SPE2
The new serial protocol, called SPE2, isn't compatible with the previous one, SGC, used in the Serial_LCD Library Suite.
To use SPE2, a program needs to be loaded to the screen:
Unfortunately, those tools are only available for Windows.
4D Systems does provide a library for Arduino but, unfortunately, I didn't manage to get it working. It crashed on both the Arduino Mega2560 and the Stellaris LaunchPad.
So the only solution was to start from scratch.
As always, the documentation provided by 4D Systems is excellent, well written, clear and accurate.
At USD 85 or even USD 125 with accessories, the screen is expensive: 10 times the cost of the LaunchPad Stellaris!
As discussed in the From Serial_LCD to LCD_screen introduction, the sceen seems over-priced for a basic usage and requires a careful price arbitration on total cost of board and screen.
However, the screen really delivers its true potential when it is used as an independent system, with the GCU acting as a MCU. The screen module can be used as:
I'm not going to discuss the first option here. The board provides 14 KB of flash and 14 KB or RAM, 13 GPIOs, PWM for sound, 2 UARTs and one I²C port, alas in master mode only.
The second option is far more interesting, with unparalleled ease of use and perfect flexibility brought by the ViSi-Genie environment for the rapid application development of an elaborate human machine interface.
This amazing new tool is called ViSi-Genie. It is only available on Windows.
So the LaunchPad Stellaris and its program can focus on I/Os management, data acquisition and processing. The LaunchPad Stellaris sends commands to and read answers from the screen module to manage interaction with the end-user.