I forgot to mention the system clock. As is in the software libraries it is a variable although in almost all applications I have written clock frequency is assumed to be constant. Then I started to program I usually defined clock frequency to be constant since it is known at compile time. I do not think the variable approach will be of much use if frequency is changed while running anyway, or do the drivers handle a change of clock frequency?
2016-10-14 12:06 GMT+02:00 Nicklas Karlsson <nicklas.karlsso...@gmail.com>: > It might you used to register call back style functions but it is a lot > simpler to tell which functions will be called if function calls are added > in interrupt handler. The software I write usually is very simple and one > of the reasons is I use the static approach, it have limitations but are > simpler then enough. > > 2016-10-14 10:42 GMT+02:00 Chris Albertson <albertson.ch...@gmail.com>: > >> You can choose to any of several libraries. I have an ARM M3 right >> now using the Arduino IDE. Can't get much simpler than that. >> Another one, an M4 here is being programmed using "mbed" library >> because I need to do something more complex that needs an RTOS but >> mbed is also very simple, certainly no call backs. >> >> But some times dynamic switching is required. I had a motor driver >> chip that has a pin that is normally an enable input but if a fault >> occurs it switches direction. the uP has to dynamically reconfigure >> a pin to read this. Also some serial busses are bidirectional >> >> That said, I think in 2016 programmers are used to using call back >> style programming because we have been writing GIUs that have to >> handle mouse events for so long. >> >> Point is that you can use this or something else if you are the one >> writing the code. >> >> On Thu, Oct 13, 2016 at 9:38 PM, Nicklas Karlsson >> <nicklas.karlsso...@gmail.com> wrote: >> >> TheCortex M is more like the Arduino then Pi. The M rarely runs an >> >> operating system and the software burned into flash and from an end >> >> user's level the software never change. You see the Arm Cortex M >> >> inside things like inkjet printers and microwave ovens and the like. >> > >> > The librarys supplied from the manufacturers have a problem here, they >> assumme everything change dynamically while in reality it does not. >> Software could be made simpler by not using there software libraries. A >> good example is with there drivers callback functions are registered >> dynamically and if this is done once during startup software will become >> simpler by just adding the function calls to the interrupt handler, with >> this method it is simple to analyse what functions will be called. >> > >> > ------------------------------------------------------------ >> ------------------ >> > Check out the vibrant tech community on one of the world's most >> > engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> > _______________________________________________ >> > Emc-users mailing list >> > Emc-users@lists.sourceforge.net >> > https://lists.sourceforge.net/lists/listinfo/emc-users >> >> >> >> -- >> >> Chris Albertson >> Redondo Beach, California >> >> ------------------------------------------------------------ >> ------------------ >> Check out the vibrant tech community on one of the world's most >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
