Hello World

[Slaxx]

Hello Community
I'm trying to get to know the program structure of the Crazyflie and therefore I want to start simple with a "Hello World" program.
My idea is to control a LED that i connected on the Breackout expansion board on some IO pin. However I'm kind if lost in the large amount of Code and I can't even find where I would add such a command and what changes I had to make to activate this register as an output.

Can anyone help me on this?

[marcus]

Hi,

Yeah, it's a big system so it may be a bit hard to dive into

For the client/crazyflie integration part you can watch these two videos (part 1, part 2) showing how to add a parameter in the Crazyflie firmware, build it, flash it and to control/log it from the client. To get an overview in text of the system architecture and communication architecture have a look at this wiki section.

But for information on how to actually drive the LED and integrate it into the firmware we don't have any doc at the moment. I would recommend having a look in the hal/src/ledseq.c file where the LEDs are controlled.

/Marcus

[Slaxx]

Ok thank you for your answer. Are the IO1-IO4 on the breakout board already configured such that they can be used to return HIGH or LOW or do they also have to be configured in the first place?

[tobias]

Unfortunately not yet, it is in the works but first we are working on merging Crazyflie 1.0 and 2.0 code. You can have a look in exptest.c where all the expansion port pins are setup and tested.

[Slaxx]

For the client/crazyflie integration part you can watch these two videos (part 1, part 2) showing how to add a parameter in the Crazyflie firmware, build it, flash it and to control/log it from the client.

It works pretty fine. Thx.

However I was wondering how to save these parameters to a file. If I go to the Tab "Log Blocks" all the Different Groups have a tick at the option "Write to File". However if I go the the directory ../conf/logdata/[date]
I only see the data of something that I set up in the Plotter. Is that normal? If yes, how would I write some data into a file without having to watch it in the Plotter?

[marcus]

1) Create a new log configuration by going to Settings->Logging configurations, select the variables you would like to log (note that there's a size limit), select the period and name, then save it
2) Go to the menu View->Tabs->Log Blocks, find your newly created block and first click the Start checkbox then the Write to file checkbox

Now the data should be written to a file in the conf/logdata directory.

[Slaxx]

Oh I see the problem. The Boxes are ticked all the time even if the data is currently not logged. If I check it in the terminal, it says Started logging or Stopped logging, but the boxes stay ticked all the time