Tired of flashing your embedded project over and over just to tweak a few values? So was [Karl], so he wrote a text editor that runs on his ARM dev board.
Having trouble wrapping your mind around the need for this kind of thing? He’s actually playing around with eLua, the embedded version of the Lua programming language. In this case the program files are being stored on an SD card. But still, moving that back and forth between computer and embedded project gets old quickly. So he invested the time to write a rudimentary text editor that he interfaces through this terminal window. Above you can see the help screen which lays out all of the applications features. Right now it sounds like the only gotcha for this is the amount of RAM it needs to run. As it stands, the editor will now work an mbed board, but it works just fine on an STM Discovery.
[Karl] loved his mbed – a tiny little ARM-powered microcontroller platform – but he wanted an interactive programming environment. BASIC just wasn’t cutting it, so he decided to bring eLua to his mbed.
When choosing an interactive development environment for microcontrollers, you generally have two choices: old or huge. Sure, there is a middle ground with Python on an ARM, but why not use something explicitly designed for microcontrollers?
To get eLua running on his mbed, [Karl] downloaded the latest version and plopped it on his mbed. The current version, 0.9, doesn’t have support for an SD card, severely limiting its usefulness. [Karl] got around this by wiring up an SD card to the mbed, giving him gigabytes of space for all his development work.
While the AVRs and PICs of the world are stuck with languages like C or worse, the new ARM boards available are more than capable of running a complete eLua development environment, with everything accessible through a terminal. [Karl] even wrote his own editor for the mbed and he’ll shortly be working on a few dozen embedded projects he has in mind.
This 32-bit computer is a project [Bogdan Marinescu] built as a contest entry. Sadly he didn’t win, but he did do an excellent job of documenting the build. Having seen several other home built PC projects we’re familiar with the challenges that go into such a thing, and he found some great solutions to each of them.
He started with an STM32F103ZET6 chip. This is an ARM Cortex-M3 processor which brings a lot of power to the playing field. That being said, generating a VGA signal would pretty much zap the usefulness of the chip for other processes so he offloaded that work on a separate Propeller chip. A microSD card serves as storage for the machine, which runs eLua (embedded Lua programming language). There is 1 MB of external RAM and a PS/2 port for keyboard interface. The system is networked thanks to an ENC28J60 Ethernet controller. Don’t miss the video after the break where you can see several demos running on the system.
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