ADD answer question 1

README.md

@@ -23,25 +23,25 @@ Test sensor libraries :
 mbed test -m DISCO_H747I -t GCC_ARM -n advdembsof_library-tests-sensors-hdc1000 --compile --run
 ```
 
-## Run static scheduling 
+## Run static scheduling
 On `.mbedignore` put at the end of the file
 ```
 static_scheduling_with_event/*
 ```
 
-On main.cpp include `"static_scheduling/bike_system.hpp"` and use : 
+On main.cpp include `"static_scheduling/bike_system.hpp"` and use :
 ```cpp
 static_scheduling::BikeSystem bikeSystem;
 bikeSystem.start();
 ```
 
 ## Run static scheduling with event queue
-On `.mbedignore` put at the end of the file : 
+On `.mbedignore` put at the end of the file :
 ```
 static_scheduling_with_event/*
 ```
 
-On main.cpp include `"static_scheduling/bike_system.hpp"` and use : 
+On main.cpp include `"static_scheduling/bike_system.hpp"` and use :
 ```cpp
 static_scheduling::BikeSystem bikeSystem;
 bikeSystem.startWithEventQueue();
@@ -53,7 +53,7 @@ On `.mbedignore` put at the end of the file
 static_scheduling/*
 ```
 
-On main.cpp include `"static_scheduling_with_event/bike_system.hpp"` and use : 
+On main.cpp include `"static_scheduling_with_event/bike_system.hpp"` and use :
 ```cpp
 static_scheduling_with_event::BikeSystem bikeSystem;
 bikeSystem.start();
@@ -63,7 +63,7 @@ bikeSystem.start();
 ## Question 1
 `If you print CPU statistics at the end of every major cycle (in the super-loop), what CPU usage do you observe? How can you explain the observed CPU uptime?`
 
-We observe a 100% usage because on each CPU cycle it compare if time is done. 
+We observe a 100% usage because on each CPU cycle it compare if time is done.
 
 ## Question 2
 `If you run the program after the change from busy wait to sleep calls, what CPU usage do you observe? How can you explain the observed CPU uptime?`
@@ -73,7 +73,7 @@ We can observe only a usage of 75% because the CPU is more on Idle with Thread s
 ## Question 3
 `If you run the static_scheduling_with_event program, what CPU usage do you observe? How can you explain the observed CPU uptime?`
 
-We observe a light usage of 1% of CPU. The CPU is now sleeping all the time and doing small task only on event. 
+We observe a light usage of 1% of CPU. The CPU is now sleeping all the time and doing small task only on event.
 
 ## Question 4
 `When you run multiple tests for computing the response time of the reset event, what do you observe? Is there an improvement as compared to the static_scheduling::BikeSystem implementation?`
@@ -84,7 +84,22 @@ We observe a light usage of 1% of CPU. The CPU is now sleeping all the time and
 
 We notice, that we miss such less event when is event driven (or not at all). But with a static scheduling the response time is still long because the reset task is call with a certain period.
 
+# Multi-tasking
+
+## Question 1
+We have computed the elapsed time between the event is sent by the interruption until it is executed :
+
+|Rtos priority            |time   |
+|---|---|
+|osPriorityBelowNormal    |13 usecs   |
+|osPriorityNormal         |13 usecs   |
+|osPriorityAboveNormal    |13 usecs   |
+
+To abtain these values, we have to consider that there is a isr thread. He dispatchs all the events from the gear device and the reset device. The rest is processed by the main thread.
+
+Main of the time, it meares these values. But sometimes, higher values can appear. These values doesn't change because there isn't often more than one event in the queue.
+
 # Issues
 When compile with GCC, the full loop of static scheduling is 2 to 3 ms faster than expected.
 This problem doesn't occur if we compile with ARMC6.
-As the acceptable delta is 2ms and the teacher test is done with GCC, we modify the delta on the test to be 3ms
+As the acceptable delta is 2ms and the teacher test is done with GCC, we modify the delta on the test to be 3ms

multi_tasking/bike_system.cpp

@@ -66,7 +66,7 @@ BikeSystem::BikeSystem()
       _resetDevice(callback(this, &BikeSystem::onReset)),
       _speedometer(_timer),
       _cpuLogger(_timer),
-      _isrEventThread(osPriorityNormal, OS_STACK_SIZE, nullptr, "ISR_Event") {}
+      _isrEventThread(osPriorityAboveNormal, OS_STACK_SIZE, nullptr, "ISR_Event") {}
 
 void BikeSystem::start() {
     tr_info("Starting Super-Loop with event handling");
@@ -144,7 +144,7 @@ void BikeSystem::init() {
     }
 
     // enable/disable task logging
-    _taskLogger.enable(true);
+    _taskLogger.enable(false);
 }
 
 void BikeSystem::gearUpTask() {