This week main project is to port FreeRTOS to the newer AEMB. In the previous weeks, the AEMB processor only fully utilizes one thread. It was the older version and the newer version actually fully utilizes two threads. I was instructed to make the necessary changes so that FreeRTOS will work on both of the two threads. First of all, what are the main differences between the old AEMB and new AEMB? The main difference is the interrupts. On the Read more
FreeRTOS was created using C. C++ offers something more than C, which are object oriented and inheritance. This is shown by the usage of class. By using class, users can create their task by simply creating the object of the class. To implement the class, I need to understand the definition of class and its properties. Class is like data structure, except that it can contain functions. So, each object created from a class will not only has the same Read more
As it turns out, there was some redundant things that I did during the upgrade to FreeRTOSV8.0.1 for AEMB2. What I did wrong last time was that I added the commits from upstream into the git repository. This was actually not required as the commits from upstream can be viewed by checking them out in the upstream itself. Since the commits were added, the git history for AEMB2 repository became extremely long and had more than 700 commits which took Read more
FreeRTOS has been using C language as its base programming language ever since it started. So, we decided to try using C++ with FreeRTOS. One of the advantages which C++ provides to FreeRTOS is the usage of class. By using class, users can supposedly create task with less syntax and coding lines. First of all, a class.hpp header file is to be created which will contain the class information of the task creation class. This is to separate the class Read more
This past week was a great struggle to try to get the quad copter to talk back to the Arduino. As discussed last week, the Arduino library DZL was tested with the NRF24L01 but the quad copter could not bind with the Arduino, or rather with the communication protocol set up with the Arduino. So a few debugging techniques were applied to the library to find out exactly how it works and where the binding process fails. Adding to that, Read more
As mentioned in the previous post, the AEMB code has to be updated. The AEMB Demo code needs to be able to run on the latest FreeRTOS V8.0.1. There are a lot of changes since V7.1.1. and these changes need to be implemented on AEMB as well. First of all, FreeRTOS V8.X.X have change the names assigned to typedefs within the core FreeRTOS code. This can be referred from http://www.freertos.org/upgrading-to-FreeRTOS-V8.html#typedefs. AEMB will need to change the relevant names to accommodate Read more
So after receiving my communicators last week, I finally got the shipment of the Arduino Uno, and yeah I know that it is in fact a cheaper Chinese clone of the Uno, the schematic and on board chip are the same, so I think its fine to test with this board for now. The NRF24L01 is a nifty little radio communicator but I have had next to zero experience with radio communcation so I thought it would be wise to Read more
The version of FreeRTOS currently being used by AEMB is long outdated and has not been updated since two years ago. The version used is V7.1.1 while the latest version is already V8.0.1. Therefore, it is time to update it. Working on a cloned git repository from AEMB FreeRTOS repository, the first thing to do is to fetch the latest revisions from the FreeRTOS upstream repository. Since the current version is V7.1.1 which contains up to revision 1750, the fetching Read more
It was a pretty busy week once again since I had to study for tests, finish lab reports and write my Logbook for this project to get signed at my university. But it was exciting to see some of my parts arrive in the mail. Apart from that, I was able to acquire another quad-copter (a slightly larger model to the one I have) from my friend at the university. However, that copter is damaged (one arm got snapped off Read more
Its been a pretty slow week in terms of meaningful progress on the project. A few tough assignments during the week and a couple of tests meant I was pretty distracted by my studies and my Arduinos still haven’t arrived which is depressing. I contacted the seller and he’s resending them, chalking it down to the previous shipment being lost. But my first toy quad copter did arrive. However, the end result was kinda disappointing and I will discuss why Read more
