A Linux-Like Shell for Your Old Arduino UNO R3
Renovation
© Lead Image © Nelli Valova, 123RF.com
Install the KernelUNO firmware on your Arduino UNO R3 and get a Linux-like shell that lets you access files and talk to the GPIO pins. You can even extend the current feature set.
The Arduino platform is an excellent environment for building lightweight microcontroller applications. Unfortunately, it's missing one nice feature that is available on Raspberry Pi OS, and that's a shell with command-line tools for accessing the hardware. Linux tools like the gpio commands from the WiringPi library [1] and I2C bus scanning using i2cdetect [2] allow Pi users to quickly find and test their hardware before they even start writing code.
The KernelUNO project [3] addresses this deficiency by offering a Linux-like shell for older Arduino modules. Features like a file/directory structure, controlling GPIO pins, reading sensors, and running simple scripts are available from the serial terminal (Figure 1). KernelUNO has the following 23 built-in commands:
- Filesystem commands:
ls,cd,pwd,mkdir,touch,cat,echo [text] > [file],rm,info [name] - Hardware commands:
pinmode [pin] [in/out],gpio [pin] [on/off],read [pin],write [pin] [high/low] - System commands:
uptime,uname,dmesg,df,free,whoami(hardcoded to root),clear,reboot,help,sh
[...]
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