Proof of concept that threads in a Real Time Operating System for the Raspberry Pi can emulate various Arduinos with help of a library that mimics the Arduino API. This will maximize the efficiency of the ArduSat platform by allowing multiple Arduinos to use dynamically asigned sensors. Please turn on the captions in the video for english subtitles.

This project is solving the ArduSat challenge.


Description

This project solves the Ardusat hardware level 3 challenge by using a Raspberry Pi running ChibiOS (a Real Time Operating System for embedded systems). Inside ChibiOS threads runs Arduino code with help of a library that mimics the Arduino platform. The RTOS can be configured to map pins and devices betwen the Raspberry Pi and the virtual Arduinos allowing the maximum use of the sensors in Ardustat. The code and configuration running on the Raspberry pi can be uploaded via serial console for remote management.

Build & Run

1. Wire the prototype

See Arduinos on the Raspberry Pi schematics

2. Install the GNU ARM toolchain

In MAC OS X you can use Yagarto and in Linux you can use yol.

3. Get ChibiOS for the RPi

git clone https://github.com/steve-bate/ChibiOS-RPi

4. Get Arduinos on the Raspbery Pi

git clone https://github.com/manuel-rabade/arduino-chibios-rpi

5. Build

cd arduino-chibios-rpi && make

cd arduino-chibios-rpi/bootloader && make

6. Setup SD card

Copy arduino-chibios-rpi/bootloader/kernel.img to the SD card. Download bootcode.bin and start.elf and copy them to the SD card.

7. Serial console

Install minicom and configure it:

  • Serial Device: /dev/ttyUSB0
  • Bps/Par/Bits: 115200 8N1
  • Hardware Flow Control: No
  • Software Flow Control: No

8. Boot

Power your Raspberry Pi and upload arduino-chibios-rpi/build/ch.bin using XModem.

Serial console

Once ChibiOS has been uploaded the following commands are available in the serial shell:

  • status get virtual Arduinos status
  • pause [arduino #] pause operation of a virtual Arduino
  • resume [arduino #] resume operation of a virtual Arduino
  • log [arduino #] get the serial buffer of a virtual Arduino
  • mem get ChibiOS memory usage
  • threads get ChibiOS threads status
  • info get ChibiOS build information
  • systime get system time
  • reboot reboot ChibiOS

Pin configuration

This project map the following Raspberry Pi pins to virtual Arduino pins:

Raspberry Pi    Virtual Arduino   Arduino pin
GPIO22          arduino0          13
GPIO7           arduino1          13
GPIO25          arduino1          12
GPIO17          arduino2          13
GPIO24          arduino3          13

Hack

arduino-chibios-rpi/main.cpp it's the entry point that spawns the threads.

arduino-chibios-rpi/arduino/arduino0.cpp, arduino-chibios-rpi/arduino/arduino1.cpp, arduino-chibios-rpi/arduino/arduino2.cpp and arduino-chibios-rpi/arduino/arduino3.cpp are the code for each virtual Arduino.

arduino-chibios-rpi/arduino-chibios-rpi/arduino/arduino0.h, arduino-chibios-rpi/arduino/arduino1.h, arduino-chibios-rpi/arduino/arduino2.h and arduino-chibios-rpi/arduino/arduino3.h are the configuration for each Arduino.

arduino-chibios-rpi/arduino/arduino.h and arduino-chibios-rpi/arduino/arduino.cpp is the library that "emulates" the Arduino plataform.

References



Project Information

License: BSD 2-Clause License
Source Code/Project URL: https://github.com/manuel-rabade/arduino-chibios-rpi

Resources

Bootloader build and SD card setup - http://www.youtube.com/watch?v=gKtXT4GJeRg
Upload, build and run - http://www.youtube.com/watch?v=D3jWURlTU5I
Prototype - https://raw.github.com/manuel-rabade/arduino-chibios-rpi/master/photo/arduinos-on-the-raspberry-pi.jpg
Schematic - https://raw.github.com/manuel-rabade/arduino-chibios-rpi/master/schematic/arduinos-on-the-raspberry-pi.png