README.md

@@ -148,6 +148,29 @@ When using Windows, run theses steps in MSYS2.
 
 # <a id="host-commands"></a> Useful and Common Commands (Host)
 
+## Build generation
+
+Replace `Debug` with `Release` for release build. Add `-G "MinGW Makefiles` or `-G "Ninja"`
+on Windows or when `ninja` should be used. You can build with `cmake --build . -j` after
+build generation. You can finds scripts in `cmake/scripts` to perform the build commands
+automatically.
+
+### Q7S OBSW
+
+```sh
+mkdir build-Debug-Q7S && cd build-Debug-Q7S
+cmake -DTGT_BSP=arm/q7s -DFSFW_OSAL=linux -DCMAKE_BUILD_TYPE=Debug ..
+cmake --build . -j
+```
+
+### Q7S Watchdog
+
+```sh
+mkdir build-Debug-Q7S && cd build-Debug-Q7S
+cmake -DTGT_BSP=arm/q7s -DFSFW_OSAL=linux -DBUILD_WATCHDOG=ON -DCMAKE_BUILD_TYPE=Debug ..
+cmake --build . -j
+```
+
 ## Connect to EIVE flatsat
 
 ### DNS
@@ -192,6 +215,12 @@ Other useful tmux commands:
   You can quit scroll mode with `q`. 
 - Kill a tmux session: run `ctrl + b` and then `k`.
 - Detach from a tmux session: run `ctrl + b` and then `d`
+- [Pipe last 3000 lines](https://unix.stackexchange.com/questions/26548/write-all-tmux-scrollback-to-a-file)
+  into file for copying or analysis: 
+      1. `ctrl + b` and `:`
+      2.  `capture-pane -S -3000` + `enter`
+      3. `save-buffer /tmp/tmux-output.txt` + `enter`
+
 
 ### SSH console
 
@@ -587,7 +616,7 @@ pscp -scp -P 22 eive@192.168.199.227:</directory-to-example-file/>/example-file
 
 More detailed information about the used q7s commands can be found in the Q7S user manual.
 
-# <a id="q7s"></a> Q7S
+# <a id="q7s"></a> Q7S OBC
 
 ## Launching an application at start-up
 
@@ -666,13 +695,31 @@ creating directories. To do this, the parition needs to be mounted.
    systemctl status example
    ```
 
-
 ## Current user systemd services
 
 The following custom `systemd` services are currently running on the Q7S and can be found in
 the `/etc/systemd/system` folder.
 You can query that status of a service by running `systemctl status <serviceName>`.
 
+### `eive-watchdog`
+
+The watchdog will create a pipe at `/tmp/watchdog-pipe` which can be used both by the watchdog and
+the EIVE OBSW. The watchdog will only read from this pipe while the OBSW will only write
+to this pipe. The watchdog checks for basic ASCII commands as a first basic feature set.
+The most important functionality is that the watchdog cant detect if a timeout
+has happened. This can happen beause the OBSW is hanging (or at least the CoreController thread) or
+there is simply now OBSW running on the system. It does to by checking whether the FIFO is
+regulary written to, which means the EIVE OBSW is alive.
+
+If the EIVE OBSW is alive, a special file called `/tmp/obsw-running` will be created.
+This file can be used by any other software component to query whether the EIVE OBSW is running.
+The EIVE OBSW itself can be configured to check whether this file exists, which prevents two
+EIVE OBSW instances running on the Q7S at once.
+
+If a timeout occurs, this special file will be deleted as well.
+The watchdog and its configuration will be directly integrated into this repostory, which
+makes adaptions easy.
+
 ### `tcfagent`
 
 This starts the `/usr/bin/agent` program to allows remote debugging. Might not be part of