I am trying to find out what is the syntax for the functions used in a library.
I have opened the Readme.TXT that seems to be in every library sub directory but is a list of keywords with no explanation as to the syntax of how to use them.
eg TimeAlarms...alarmRepeat()...How do I find out what variables and in what sequence should go in the brackets?
It really depends on the library. There is documentation for most of the official Arduino libraries here:
As for 3rd party libraries, it's different for each one. If you installed the library via the Arduino IDE's Library Manager (Sketch > Include Library > Manage libraries...), you should click the "More info" link for that library entry and search from there. Some of them will have comprehensive documentation in their readme file. Others will not store the documentation in the readme but it will have a link to it. Sometimes there is no link. An easy to overlook place where documentation is sometimes found is the "Wiki" tab of the GitHub repository. Usually libraries will come with some example sketches that demonstrate usage. You will find these sketches under the Arduino IDE's File > Examples > {library name} menu after installing the library.
Sometimes there is no documentation at all. The library source code will always be the definitive reference. You will find the function declarations in the .h file(s). That will provide a list of the functions and their parameter types, perhaps with some explanatory comments. The function definitions will usually be in the .cpp files. That is where to go to get a full understanding of how the functions work.
eg TimeAlarms...alarmRepeat()...How do I find out what variables and in what sequence should go in the brackets?
From the TimeAlarms readme.txt
Alarms can be specified to trigger a task repeatedly at a particular day of week and time of day:
Alarm.alarmRepeat(dowMonday, 9,15,0, MondayMorningAlarm);
This would call the function WeeklyAlarm() at 9:15am every Monday.
Mind you, they have got the name of the function that will be triggered wrong
Or, of course, look at the examples
Alarm.alarmRepeat(8,30,0, MorningAlarm); // 8:30am every day
Alarm.alarmRepeat(17,45,0,EveningAlarm); // 5:45pm every day
Alarm.alarmRepeat(dowSaturday,8,30,30,WeeklyAlarm); // 8:30:30 every Saturday
Another alternative is to look at the .h file which every library will have
AlarmID_t alarmRepeat(time_t value, OnTick_t onTickHandler); // trigger daily at given time of day
AlarmID_t alarmRepeat(const int H, const int M, const int S, OnTick_t onTickHandler); // as above, with hms arguments
AlarmID_t alarmRepeat(const timeDayOfWeek_t DOW, const int H, const int M, const int S, OnTick_t onTickHandler); // as above, with day of week
The parameters are fairly obvious
I submitted a pull request to fix the callback function name errors in the readme:
Thanks
Do I use the IDE to open the .h file?
It seems to be the ONE that will answer all my questions. Function and parameters and type of data the parameters need to be.
I used the examples to learn but then when I find another sketch with the same library, I find that that programmer used a function that I had never seen and it would have simplified what I wanted to do if I had known about it. :o
HermanJFourie:
Do I use the IDE to open the .h file?
No, you can't open it with the Arduino IDE. It's just a text file so you can open it with any text editor of your choice.
HermanJFourie:
I used the examples to learn but then when I find another sketch with the same library, I find that that programmer used a function that I had never seen and it would have simplified what I wanted to do if I had known about it. :o
I agree that example sketches are no substitute for a comprehensive reference. Unfortunately a lot of Arduino library authors seem to think they are sufficient documentation.