It’s not only the developers of smartphones and tablets who feel compelled to use colour LCDs with appealing and informative graphical user interfaces, but also those designing applications for smaller production runs. By Herbert Demmel, founder and CEO of demmel products.
In many industrial electronic applications, a display is essential for showing the device’s status or providing operational guidance for the user. While simple character displays were considered to be sufficient in the past, today’s customers expect aesthetically appealing and user-friendly graphic interfaces.
Conventional development with ‘dumb’ LCDs requires significant resources and experience in terms of both hardware and software. State-of-the-art colour LCD panels typically require a powerful 32-bit microcontroller, extensive RAM and flash memory and a display controller. Regardless of whether the LCD-driving hardware is developed from scratch or a ready-to-use board is adapted to fit the needs of the desired application, time and labor investments can quickly get out of hand.
For appealing designs, expensive graphic libraries have to be purchased and developers must either bring the know-how with them or be trained to set up and implement third-party software in their own – often proprietary – hardware. Support from LCD manufacturers can hardly be expected, and hardware specification and datasheets from the almost exclusively Asian suppliers often lack important details.
For smaller production runs the implementation of a colour display can therefore involve over nine months of development time even for experienced design engineers. Overall development costs and subsequent retail prices can make a product unmarketable.
In times of crisis, development firms tend to focus on their core competencies and often employ ready-to-use solutions even for larger production quantities, instead of engaging in risky and lengthy in-house development projects. Often their engineers lack the necessary skills for creating attractive display applications. Furthermore, using out-of-the-box solutions is the most reliable way to calculate overall development costs.
All inclusive displays
The Intelligent LCDs (iLCDs) developed by demmel products represent an entirely different development approach: all components necessary for the operation of the display have already been integrated into the iLCD. They enable users to store any Windows font, static and animated graphics, text templates and macros on the iLCD controller’s 32Mbyte flash memory. Graphics or user data can also be saved to a MicroSD card. iLCDs require none of the extensive hard and software development and pixel-based programming that conventional ‘dumb’ LCDs do, making it extremely simple to design an attractive screen layout. Using iLCD technology, electronics designers can develop appliances with a touch panel display within a few days, even if the application is run on a 50 cent processor.
Importantly, however, iLCDs are not embedded PCs; as such video playback, streaming of screen-filling real-time data, or using an iLCD as a monitor for a Windows PC is not supported. Since development costs in high-volume production runs represent a far lower percentage of total costs, using iLCD shows the greatest benefit for low to medium quantities.
All demmel products’ iLCD panels offer USB, RS232, I2C and SPI ports and an optional Ethernet board is available for TCP/IP communication. All models need only a single 5 volt power supply, but an optional 3.3 volt version is available for most colour iLCDs.
Colour iLCDs are currently available in seven form factors of 2.8, 3, 3.5, 4.3, 5.7, 7 and 10.2 with resolutions of 240x320 up to 1024x600 pixels. All models can be connected via the same single FFC connector and use the same command set; therefore they are easily interchangeable. Thanks to the low-cost models up to 3, even price-sensitive applications and higher-quantity production runs can be equipped with a colour display.
Using conventional LCDs, any discontinued model would lead to extensive workload and costs for developers who must adapt their application to the new display. Working with iLCDs, on the other hand, this financial and personnel overhead is taken off the customers' shoulders. demmel only employs LCDs with a guaranteed lifetime of at least three years and maintains close ties to several global LCD suppliers. As a result, a potential end-of-life issue for any LCD can be perceived as early as possible and a re-design of the iLCD is initiated immediately. Such a re-design does not require the customer to change anything at all in the existing hardware or software. Since the launch of the colour iLCD product line six years ago, no colour iLCD model has had to be decommissioned.
There are more than 200 easy-to-learn commands available to control iLCDs, enabling developers to carry out desired tasks quickly and easily. Text commands make it easy to display aligned (left/right justified, horizontally and/or vertically centred) and formatted strings. Text output can be word-wrapped automatically and may contain ANSI control sequences for fast and comfortable terminal implementation. Text messages can be placed in the iLCD's memory too, allowing for reduced communication overhead and supporting multi-language applications.
Graphic commands paint graphics stored in the iLCD at any desired position and control up to eight animated graphics per screen. The number of images is limited only by memory, which can be extended using the MicroSD card.
Touch screen handling is also fully integrated into the instruction set. Up to 64 touch fields per screen can be defined in any size and assigned to a character that is subsequently sent to the application when pressed or released. In addition, touch fields can automatically invoke macros stored in flash memory.
Viewports for customised segmentation of the display in screen areas and the ability to rotate texts and graphics independent of the screen orientation enables the user to improve organisation of the screen layout.
Screen memory commands support multiple frame buffers which can be used simultaneously. Drawing to a hidden screen and subsequently showing this screen with a single command facilitates a very fast screen update.
The free, easy-to-use Windows-based Integrated Development Environment (IDE) iLCD Manager XE represents a milestone in the development of graphical user interfaces and means there is no need to learn a programming language. The iLCD Manager XE enables the user to convert any Windows font, Bitmap, JPEG as well as static and animated GIF images with a few mouse clicks and then transfer the data into the iLCD’s flash memory. All iLCD models can be connected via USB, RS232 or Ethernet, no low-level driver software is required.
With iLCD Manager XE, designing applications for touch screen iLCD panels in practically no time has never been easier. The software provides a modern and very intuitive design and supports the entire iLCD product line.
Thanks to sophisticated features such as Parameter Completion and Syntax Checking/Highlighting, no programming skills are required to design state of the art graphical interfaces. A customisable GUI and multi-threading provide for comfortable and fast application development. It can even be evaluated without iLCD hardware.
Some sample source code for loading raw flash-data into the iLCD panel is available as well. It compiles on Windows and Linux, can easily be adapted to the user’s needs and may be included in the application’s software to update the iLCD’s flash data in the field.
Intelligent displays are currently used in medical electronics, industrial and elevator control systems, for measurement equipment and in a wide array of other application areas and can be designed-in to practically any application needing a graphical display. In many cases existing applications with simple monochrome character displays can be refurbished easily by adding a colour iLCD without having to change significant parts of the application; providing a slow RS232 port and a 5V power supply is often sufficient for creating a ‘new’ device.
After a successful local product launch, companies often decide to enter foreign markets which, in most cases, involves considerable adaptation to the existing application firmware to provide foreign-language capability. Since an iLCD can store all required text components in the flash memory, the application firmware does not have to be changed even if another language with different fonts is used. By using iLCDs, all multi-language messages can be stored into the flash memory. The required language can be set by using a single software command.
##IMAGE_4_R##To keep iLCDs at the cutting edge of technology, a new generation of colour models is currently being designed. Equipped with a new state-of-the-art processor, execution times and transmission rates will be significantly improved. The enhanced panels will be fully compatible to their predecessors in terms of electrical as well as mechanical specifications and can be purchased for the same price. The iLCD panels' hard- and firmware as well as the free setup software are continuously being improved in order to be able to provide well-conceived and innovative solutions.
Evaluation kits are available for all models. These contain all necessary cables, a power supply and a CD with setup and test software enabling the user to connect the iLCD to a PC and run an application within a few hours.
Intelligent LCDs enable companies to reduce costs and shorten development time. Accelerated time-to-market and enhanced flexibility provide further convincing arguments for the implementation of ready-to-use solutions in display development projects.
Author profile: Herbert Demmel is the founder and CEO of demmel products gmbh which is headquartered in Vienna, Austria and was established in 1988. Demmel holds an Engineering degree in “Industrial Electronics and Control Technology” from the Technical University of Vienna, Austria.