raspberry pi: setup and minor troubleshooting added

wiki/linux/raspberry_pi.md

@@ -2,6 +2,29 @@
 
 A [Rapberry Pi](https://www.raspberrypi.com) is a single board comuter.
 
+## Setup
+
+For setting up a classic Raspberry Pi an SD card is needed that contains the operating system.
+
+For this an image has to be flashed.
+The images of the operating systems can be found on the
+[official website](https://www.raspberrypi.com/software/operating-systems).
+A command to flash may look similar to the following example, where `<img-path>` is the path to the
+image and `<disk-path>` is the path to the device to flash to (for example `/dev/sdb1`).
+
+```sh 
+dd if=<img-path> of=<disk-path> status=progress
+```
+
+This however can also be done using the Raspberry Pi imager - which most
+[package managers](/wiki/linux/package_manager.md) package under `rpi-mager`.
+It too can also be found on the [official website](https://www.raspberrypi.com/software).
+When using the imager as a non-root user this user may have to be given rights to access disks or
+at least the SD card as described in the
+[corresponding article](/wiki/linux/disk-management.md#accessing-disks-as-user).
+
+The setup using the imager is guided and easier.
+
 ## Hardware Additions
 
 There are various hardware additions which can be used with the Raspberry Pi.
@@ -51,7 +74,7 @@ The second command is optional but recommended and takes the path to this `.har`
 The third and final command compiles the (optimized) `.har` model, which is given as the input, and
 outputs the final `.hre` model, which then can be used with the Hailo AI module.
 
-```sh 
+```sh
 hailo parser tf <path-to-tf-model>
 hailo optimize --use-random-calib-set <path-to-har-model>
 hailo compiler <path-to-optimized-har-model>