The Raspberry PI (RPi) is an ARM-based credit-card-sized single board computer. It costs around $35 (PI 2) and therefore it is a very attractive choice for amateur astronomers to control their equipment either locally or remotely. It can be used over Ethernet or WiFi to control your equipment remotely. 

Due to power limitations of the RPi, it is recommended to connect all devices to a powered USB hub. INDI Library v1.2.0 packages in addition to 3rd party drivers are available for the RPi (Raspbian Jessie, Wheezy packages are no longer offered). Furthermore, if you install Ubuntu Mate for Raspberry PI 2, you can get all the bleeding edge INDI and KStars directly from the Ubuntu INDI PPA, no need to download and install packages manually!

You typically would run an INDI server on the RPi and connect to it remotely from Ekos. While it is technically possible to build Ekos in RPi, it would not run smoothly; therefore it is recommended to run INDI server on the RPi and Ekos on a more powerful machine.

The following steps are applicable to RPi running the Raspbian OS:

    1. Install the dependencies:
      sudo apt-get install cdbs libcfitsio3-dev libnova-dev libusb-1.0-0-dev libjpeg-dev libusb-dev libtiff5-dev libftdi-dev fxload libkrb5-dev libcurl4-gnutls-dev dcraw libgphoto2-dev libgsl-dev dkms libboost-regex-dev libgps22 libdc1394-22-dev
    2. Download INDI Library for RPi
    3. Extract and Install INDI Library:
      tar -xzf libindi_1.2.0_rpi.tar.gz
      cd libindi_1.2.0_rpi
      sudo dpkg -i *.deb

Included in the INDI Library for RPi are INDI servers, tools, and drivers. The following are some of the drivers in the package. For a complete list, please check the devices page:

EQMod Driver indi_eqmod_telescope
Atik CCD Driver indi_atik_ccd
GPhoto Driver (for DSLRs) indi_gphoto_ccd
Starlight Xpress Driver indi_sx_ccd, indi_sx_wheel, indi_sx_ao
QSI Driver indi_qsi_ccd
QHY Driver indi_qhy_ccd
Meade DSI Pro I/II Driver indi_dsi_ccd
Atik CCD Driver indi_atik_ccd
SBIG Driver indi_sbig_ccd
Fishcamp Driver indi_fishcamp_ccd
Apogee Driver indi_apogee_ccd
ZWO Optics ASI Driver indi_asi_ccd
AAG Cloud Watcher Driver indi_aagcloudwatcher

To run INDI server:

indiserver -v -m 100 driver_executable

Replacedriver_executable with the actual INDI driver executable. For example, to run INDI server with EQMod, Atik CCD, and Joystick driver:

indiserver -v indi_eqmod_telescope indi_joystick indi_atik_ccd

This will start INDI server on the RPi on port 7624 by default. You can then connect to the INDI server from Ekos/KStars or any INDI compatible client.

You should power up your Raspberry Pi from the same USB hub you are connecting your CCD to. Powering Raspberry Pi with its own power supply will result in your CCD and Raspberry Pi do not have common ground (GND). This leads to non-zero voltage potential on all wires between your CCD and Raspberry Pi, including data lines. The noise identified on the images represents the current related to this non-zero voltage potential.

Installing the Guide Star Catalog to work with the indi_simulator_ccd driver

If you are planning to use the indi_simulator_ccd driver and need to retrieve simulated images of star fields you have to install de Guide Star Catalog (GSC) on your RPi. To do so, follow the next steps:

  1. Create a folder to download and compile the GSC:
    mkdir gsc
    cd gsc
  2. Download both the Data (more than 200MB!) and the Source files of the 1.2 version:
    wget -O bincats_GSC_1.2.tar.gz
  3. Untar (uncompress) the downloaded data and source files:
    tar -xvzf bincats_GSC_1.2.tar.gz
  4. Compile the source code:
    cd src
    Ignore the error messages regarding some *.o files that cannot be removed.
  5. Rename the executable and copy it to the /usr/bin directory:
    mv gsc.exe gsc
    sudo cp gsc /usr/bin/
    cd ..
  6. Copy the regions.* files from the bin directory to the base gsc directory:
    cp ~/gsc/bin/regions.* ~/gsc
  7. Update your .bashrc to set the GSCDAT environment variable:
    cp ~/.bashrc ~/.bashrc.copy
    echo "export GSCDAT=~/gsc" >> ~/.bashrc
  8. Log out and log in again into your RPi for the environment variable to take effect.
  9. Launch the indiserver with the indi_simulator_ccd driver and test it with your favourite client!:
    indiserver indi_simulator_ccd