more README

README.md

@@ -4,3 +4,19 @@ FSFW From Zero Workshop
 This workshop gives an introduction to the Flight Software Framework,
 starting from a simple hello world program in C++. As such, it it also suitable
 for C++ beginners.
+
+Start by cloning this repository and updating the submodules to also clone
+the [Flight Software Framework](https://egit.irs.uni-stuttgart.de/fsfw):
+
+```sh
+git clone https://egit.irs.uni-stuttgart.de/fsfw/fsfw-from-zero.git
+git submodule init
+git submodule update
+```
+
+# Overview
+
+This workshop does an incremental build-up of a simple software which
+is similar to an On-Board Software.
+
+It is organised in chapters which have a task description.

start/01-tasks.md

@@ -0,0 +1,80 @@
+# Threads and Tasks
+
+A satellite is a complex system which usually has a lot of tasks which need to be done
+simulatenously by a dedicated On-Board Computer (OBC). This can include for example:
+
+- TMTC handling. This includes Telecommand (TC) reception and execution, and the (autonomous)
+  generation of Telemetry (TM)
+- Control Operations, for example execution of the Attitue Control System (ACS) loop
+- Handling of connected physical devices like sensors or payloads
+
+Usually, these systems oftentimes have soft and even hard real-time requirements where longer delays
+are not allowed and the system has an upper bound for response times.
+
+This basically means that any software which does multiple non-trivial tasks needs a
+(real-time) operating system to perform multiple tasks consecutively, with deterministisc
+guarantees that these tasks are performed within a certain temporal bound.
+
+Some common operating system in the Space domain able to do this:
+
+- FreeRTOS for smaller MCUs (SOURCE)
+- Embedded Linux (EIVE)
+- RTEMS (FLP)
+
+All these operating system use threads or tasks as the basic worker unit which is executing code.
+This chapter first introduces threads as they are exposed by the C++ standard library.
+After that, the code is transitioned to use the abstraction provided by the framework.
+
+## 1. Scheduling a basic task using the C++ `std::thread` API
+
+The goal of this task is to set up a basic thread which prints the following
+string every second: "Executing Dummy Task".
+
+ - [std::thread API](https://en.cppreference.com/w/cpp/thread/thread)
+ - [Delaying a thread](https://en.cppreference.com/w/cpp/thread/sleep_for)
+
+## 2. Changing to the concept of executable objects
+
+Threads generally expect a function which is then directly executed.
+Sometimes, the execution of threads needs to be deferred. For example, this can be useful
+if the execution of tasks should only start after a certain condition.
+
+Also, it might become useful to model any task in form of a class. An instantiation
+of that class would then be an executable object. This is precisely what the framework
+exposes in form of the [`ExecutableObjectIF`](https://documentation.irs.uni-stuttgart.de/fsfw/development/api/task.html).
+
+It also offers a unform API to execute periodic tasks in form of the
+[`PeriodicTaskIF`](https://egit.irs.uni-stuttgart.de/fsfw/fsfw/src/branch/master/src/fsfw/tasks/PeriodicTaskIF.h).
+
+These tasks can then be created using the
+[`TaskFactory`](https://egit.irs.uni-stuttgart.de/fsfw/fsfw/src/branch/master/src/fsfw/tasks/TaskFactory.h) singleton.
+
+An arbitrary number of executable objects can then be passed to a periodic task. These objects
+are then executed sequentially. This allows a granular design of executable tasks.
+For example, important tasks get an own dedicated thread while other low priority objects are
+scheduled consecutively in another thread.
+
+The goal of this task is to convert the code from task 1 so the [std::thread]
+API takes an executable object to move to a more object oriented task approach. 
+The printout of the threaf should remain the same.
+
+It is recommended to pass this executable object into the [std::thread] directly.
+
+ - [std::reference_wrapper](https://en.cppreference.com/w/cpp/utility/functional/reference_wrapper)
+    to pass referneces to the [std::thread] API.
+
+As a bonus task, you can make your executable object implement a
+[MyExecutableObjectIF] interface class. An interface class is
+an [abstract class](https://en.cppreference.com/w/cpp/language/abstract_class) which
+only contains pure virtual functions. As such, it can only be implemented by other
+objects and describes a certain API contract an object has to fulfill.
+
+## 3. Using the framework abstractions
+
+As described before, the framework provides task abstraction with some advantages
+
+- Task execution can be deferred until an explicit `start` method is called
+- Same uniform API for multiple operating systems
+
+The goal of this task is to implement the task specified in 1 using the
+abstractions provided in step 1.

start/main.cpp

@@ -1,11 +1,10 @@
 #include <iostream>
 
 #include "fsfw/serviceinterface.h"
-#include "FSFWConfig.h"
+#include "fsfw/FSFW.h"
 
 using namespace std;
 
-
 #if FSFW_CPP_OSTREAM_ENABLED == 1
 ServiceInterfaceStream sif::debug("DEBUG", false);
 ServiceInterfaceStream sif::info("INFO", false);
@@ -15,5 +14,4 @@ ServiceInterfaceStream sif::error("ERROR", false, true, true);
 
 int main() {
     cout << "hello world!" << endl;
-
-}
+}