If you have something that just needs to switch something on / off once in a while( less than 200 Hz ) why would you need to complicate things ?
If you need fast though, a PRU + mmap can achieve fairly "insane" speeds. 10Mhz or better should not be a problem. On Mon, Aug 18, 2014 at 12:18 PM, Tim Cole <[email protected]> wrote: > So, I'm guessing it's a case of sacrificing performance for portability > and robustness. My first reaction is that it seems odd, but then again --- > make it work before you make it faster. > Thanks! > > > > On Monday, August 18, 2014 1:54:39 PM UTC-4, Jerônimo Lopes wrote: > >> I think... >> >> It's one of UNIX system base, that everything is a file. >> It is a common way of doing things in different platforms. For example: >> gpio registers in 8051 are different from PIC, and different from AVR, and >> so on. On a Linux (at least at user space), there is a common interface to >> access gpio. Gives you much more portability. You can run the same code in >> different processors. >> >> Jerônimo Lopes >> >> >> >> 2014-08-17 1:01 GMT-03:00 Tim >> >>> Greetings all, >>> >>> I've been playing with software and hardware for 30+ years, but I'm new >>> to Linux and embedded Linux systems. The code snippets I've been able to >>> find for GPIO access all seem use file I/O functions. I've never seen this >>> approach before -- I'm accustomed to reading and writing processor >>> registers. The file I/O approach seems strange to me, but I'm new here, and >>> there's a *lot *that seems strange. >>> >>> So, can someone explain why the file I/O approach is used? Is this a >>> typical technique for Linux systems, or something particular to ARM >>> processors? I suppose it doesn't really matter, but I prefer to understand >>> why things are done as they are. >>> >>> Thanks very much, folks. >>> >>> Yours in newness, >>> Tim >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
