Love ’em or hate ’em, sometimes your embedded project needs a menu system. Rather than reimplement things each and every time, [sgall17a] put together a simple GUI menu system in Micropython that can be reused in all sorts of projects. The approach uses tables to define the menus and actions, and the demo program comes with a pretty good assortment of examples. Getting up to speed using this module should be fairly easy.
The hardware that [sgall17a] chose to demonstrate the concept couldn’t have been much smaller — it’s a Raspberry Pi Pico development board, an OLED 128 x 64 pixel display, and a rotary encoder with built-in push-button switch (it’s also been tested on ESP32 and ESP8266 boards). The widget under control is one of the commonly available Neopixel development boards. The program is hosted on GitHub, but beware that it’s under development so there may be frequent updates.
This is a good approach to making menus, but is often rejected or not even considered because of the overhead cost of developing the infrastructure. Well, [sgall17a] has done the hard work already — if you have an embedded project requiring local user setup, check out this module.
We’ve had something of an anniversary of late, and it’s one that will no doubt elicit a variety of reactions from our community. It’s now 25 years ago that Windows 95 was launched, the operating system that gave the majority of 1990s PC users their first taste of a desktop-based GUI and a 32-bit operating system.
To the strains of the Rolling Stones’ Start me up, Microsoft execs including Bill Gates himself jubilantly danced on stage at the launch of what was probably to become the company’s defining product, perhaps oblivious to the line “You make a grown man cry” which maybe unwittingly strayed close to the user experience when faced with some of the software’s shortcomings.
Its security may seem laughable by the standards of today and the uneasy marriage of 16-bit DOS underpinning a 32-bit Windows operating system was clunky even in its heyday, but perhaps now is the best time to evaluate it unclouded by technical prejudice. What can we see of Windows 95 in the operating systems we use today, and thus from that can we ask the question: What did Windows 95 get right? Continue reading “Start Me Up: What Has The Windows 95 Desktop Given Us 25 Years Later?”
Not every programmer likes creating GUI code. Most hacker types don’t mind a command line interface, but very few ordinary users appreciate them. However, if you write command line programs in Python, Gooey can help. By leveraging some Python features and a common Python idiom, you can convert a command line program into a GUI with very little effort.
The idea is pretty simple. Nearly all command line Python programs use
argparse to simplify picking options and arguments off the command line as well as providing some help. The Gooey decorator picks up all your options and arguments and creates a GUI for it. You can make it more complicated if you want to change specific things, but if you are happy with the defaults, there’s not much else to it.
At first, this article might seem like a Python Fu and not a Linux Fu, since — at first — we are going to focus on Python. But just stand by and you’ll see how this can do a lot of things on many operating systems, including Linux.
Continue reading “Linux Fu: Python GUIs For Command Line Programs (Almost) Instantly”
These days, working with a display in software is fairly easy. Thanks to the convenience of the modern OS, we’re blessed with graphical user interfaces, where things such as buttons and windows and text are all taken care of for us. Of course, once you start to wander off the beaten track, particularly in embedded systems with no GUI, things can get a little more difficult. For these situations, [JSBattista] wrote some code to blast text directly to the Linux framebuffer.
It’s a project borne out of necessity. Working with a Raspberry Pi with no X server, it was found that the console text size made it difficult to display data. By writing directly to the framebuffer, it would be possible to display text of a larger size without having to implement a full GUI, and overheads could be kept to a minimum.
Working in this manner comes with some limitations. Glyphs are taken from an array in bitmap format, rather than font files. In this case, a font akin to that of the Alien sentry gun interface was chosen, for an attractive sci-fi look. Lowercase characters are currently unimplemented. Testing thus far has been on Raspberry Pi and Beaglebone non-GUI systems, with performance varying depending on platform.
It’s a project we suspect might prove useful to the developers of lightweight embedded systems. It’s something that may take some tweaking and experimentation to implement, but the hacker set rarely shy away from a challenge. If you’re eager to get down and dirty with some heavy programming, this tutorial on Linux graphics will help.
There was a time when writing embedded systems meant never having to deal with graphical user interfaces, and spending long hours trying to free up a dozen bytes of ROM to add a feature. Nowadays, an embedded system is likely to have a screen and what would have been a huge amount of memory even for a PC a scant decade ago. Qt has long been a popular choice for building software on desktop platforms, and — while not as popular — has even run on phones for a while. Now there’s Qt for MCUs which is clearly targeting the IoT market that everyone is trying to capture. You can see the glitzy video for the new product, below.
We generally like Qt, and the move recently has been towards an HTML-like markup language called QML instead of directly manipulating widgets. We guess that’s a good thing. However, Qt isn’t just for user interfaces. It provides a wide range of services in a straightforward way
Continue reading “Qt Arrives For Small Computers”
We featured [Fabrizio Di Vittorio]’s FabGL library for the ESP32 back in April of this year. This library allows VGA output using a simple resistor based DAC (3 resistors for 8 colors; 6 resistors for 64 colors), and includes functions for PS/2 mouse and keyboard input, a graphics library, and many of the miscellaneous functions you might need to develop games on the ESP32. Now, a GUI interface library has been added to ease application development.
The GUI, of course, runs on the VGA output. The library includes what you’d expect from a minimal windowing GUI, like keyboard and mouse support, windows with the usual minimize/maximize/close controls, and modal and message dialog boxes. For input controls, there are labels, text boxes, buttons, radio buttons, checkboxes, normal and editable combo boxes, and listboxes — you know, pretty much everything you need to develop a modern GUI application. All the code is open-source (GPL 3.0) and in the GitHub repo.
While the original FabGL had a game-development orientation, the addition of this new GUI functionality opens up a new range of applications. If you want to find out more about using the FabGL library, you can check out our previous coverage of the mostly game-oriented functions.
You can get a look at the new GUI functions in action in the video, after the break.
Continue reading “ESP32 Gets Advance Windowed Apps Using This VGA GUI Library”
The 6th Generation iPod Nano was something of a revelation on launch. Packing a color screen, audio hardware, and a rechargable battery into a package no bigger than a large postage stamp remains impressive to this day. They’re now being used in various maker projects for their displays, but if you’re doing so, you might want to think about how you’re going to build a graphical interface. Not to worry – just grab an ESP32 and the right GUI library, and you’re on your way.
The Nano screen uses a MIPI DSI interface, which isn’t the easiest thing to use directly with the ESP32. Instead, a SSD2805 interface chip converts parallel input data to MIPI DSI signals to drive the display. Driving the display is only part of the game, however – you need something to display on it. Combining the LittlevGL GUI library with the screen’s touchpad makes creating a full graphical interface easy.
Hacked screens are something we don’t see as much these days, with the proliferation of display products aimed directly at the maker market. However, it’s always awesome to see a successful hack pulled off well. We’ve seen the display reverse engineered, too – and it certainly wasn’t easy.