====== APFEL/HV raspberry pi======

Stand: 18/8/2021

=== Configuration ===

  * Start with a raspbian image
  * Set up a user with username: ''pi'', and password: standard ''agmaas'' password
  * To enable the I2C bus and set the correct frequency, uncomment the following line from ''/boot/config.txt''

  dtparam=i2c_arm=on
and modify it to
  dtparam=i2c_arm=on,i2c_arm_baudrate=400000

=== Software installation ===

  * Create a directory ''/home/pi/apfel_dev''
  * In that directory clone the following repositories
    * ''https://gitlab.rlp.net/emp/apfel_interface''
    * ''https://gitlab.rlp.net/emp/hv_control''
  * Compile with ''make'' both repositories
  * Add the following lines to ''/etc/rc.local''

  /home/pi/apfel_dev/hv_control/start_hv.sh
  /home/pi/apfel_dev/apfel_interface/scripts/start_apfel.sh

  * Add the following lines to ''/home/pi/.bashrc''

  HVDIR=$HOME/apfel_dev/hv_control
  APFELDIR=$HOME/apfel_dev/apfel_interface
  
  alias watch_hv='$HVDIR/watch_hv.sh'
  alias start_hv='$HVDIR/start_hv.sh'
  alias watch_apfel='$APFELDIR/scripts/watch_apfel.sh'
  alias start_apfel='$APFELDIR/scripts/start_apfel.sh'

  * Reboot the pi to see if everything worked. On startup, the APFEL and HV control programs should be started


=== Service scripts ===

  * Through the aliases **''watch_hv''** and **''watch_apfel''**, it is possible to see the output of the respective servers. The log files to which the servers write to are:

  /home/pi/apfel_dev/hv_control/hvlog.{out,err}
  /home/pi/apfel_dev/apfel_interface/apfellog.{out,err}

  * The servers can be killed and restarted through the aliases **''start_hv''** and **''start_apfel''**.
  * Without arguments, the scripts check if there are running server processes and if so exit with an output like:

  n. of server processess: 2
  n. of watch processess: 2
  processes running, kill first

  * To kill the processes, call the aliases with the argument ''-kill'' (e.g. ''start_hv -kill''). 
  * **Only for ''start_apfel''**, it is possible to start the server with the verbose flag set by invoking the alias with ''start_apfel -v''.