rbarbera / astrolink4pi

Astroberry server hardware platform with focuser control and regulated/switchable outputs.

AstroLink 4 Pi

AstroLink 4 Pi micro features:

• Focuser
  • DRV8825 driver support for Moonlite / Robofocus / AstroLink geared unipolar steppers and bipolar microstepping up to 1/32
  • Absolute position control
  • Relative position control
  • Forward / Reverse direction configuration
  • Customizable maximum absolute position (steps)
  • Customizable maximum focuser travel (mm)
  • Backlash compensation
  • Speed control
  • Focuser info including: critical focus zone in μm, step size in μm, steps per critical focus zone
  • Automatic temperature compensation based on DS18B20 temperature sensor
  • Stepper movement abort
  • 6 pin RJ12 stepper output
  • embedded real time clock (AstroLink 4 Pi version 2 only)
• Power outputs
  • Two switchable 12V DC outputs, 5A max each
  • One permanent 12V DC output
  • Two PWM regulated RCA outputs, 3A max each
  • One adjustable DC output 3-10V, 1.5A max
  • Configurable labels
• Astroberry System
  • Provides system information such as local system time, UTC offset, hardware identification, CPU temperature, uptime, system load, hostname, local IP, public IP
  • Allows for system restart and shut down (Supported on linux operating system only. Requires advanced configuration of sudo to allow restart & shutdown without password)
• Other
  • Internal fan controlled by GPIO pin - automatic work

Source

https://github.com/astrojolo/astrolink4pi

Requirements

• INDI available here http://indilib.org/download.html
• CMake >= 2.4.7

Installation

If you have a fresh SD card with astroberry system, then it is worth to update the system with command

sudo apt update && sudo apt upgrade && sudo apt dist-upgrade

Download and install required libraries before compiling AstroLink 4 Pi. See INDI site for more details. In most cases it's enough to run:

sudo apt-get install cmake libindi-dev libgpiod-dev

You also need to enable pigpiod daemon, that is preinstalled with astroberry, but not enabled at startup:

sudo systemctl enable pigpiod

and restart the device. Then you can compile the driver:

git clone https://github.com/astrojolo/astrolink4pi
cd astrolink4pi
mkdir build && cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr ..
make

Or update to latest version:

cd ~/astrolink4pi/build/
git pull
cmake -DCMAKE_INSTALL_PREFIX=/usr ..
make

You can install the drivers by running:

sudo make install

OR manually installing files by running:

sudo cp indi_astrolink4pi /usr/bin/
sudo cp indi_astrolink4pi.xml /usr/share/indi/

After these steps AstroLink 4 Pi driver will be visible in the Aux devices lists under Astrojolo group.

Real Time clock enabling - only version 2

To enable automatic synchronization of the RTC embedded in the version 2 of AstroLink 4 Pi you need to edit the file

sudo nano /etc/rc.local

and add following line before exit 0 statement at the file end

echo ds1307 0x68 > /sys/class/i2c-adapter/i2c-1/new_device

After restart the astroberry system time will be synchronized with embedded DS1307 clock. Check hwclock help to find more options, like time adjustments and synchronization:

hwclock -h

How to use it?

Enable 1-Wire interface using raspi-config or adding 'dtoverlay=w1-gpio' to /boot/configure.txt for temperature compensation support (reboot required). Run Kstars and select AstroLink 4 Pi (Aux section) in Ekos profile editor. Then start INDI server in Ekos with your profile, containg AstroLink 4 Pi drivers. Alternatively you can start INDI server manually by running:

indi_server indi_astrolink4pi

Start KStars with Ekos, connect to your INDI server and enjoy!

Note that your user account needs proper access right to /dev/gpiochip0 device. By default you can read/write only if you run driver as root or user who is a member of gpio group. Add your user to gpio group by running sudo usermod -a -G gpio $USER

To use restart/shutdown functionality add this line to your /etc/sudoers file or /etc/sudoers.d/010_astroberry-nopasswd (this assumes you run INDI server as astroberry user):

astroberry ALL=(ALL) NOPASSWD: /sbin/reboot, /sbin/poweroff

For custom labels you need to save configuration and restart the driver after changing relays' labels.

AstroLink 4 Pi images