Re: [beagleboard] Which Real Time Operating Systems Can I run on Beagle Bone Black?
In my images, the ARM core is running motion and trajectory planning in a 1 ms (configurable) loop, using the Xenomai real-time patches. If you don't have something like Xenomai or PREEMPT_RT patched into the stock Linux kernel, the 1 mS loops do not execute at the proper time. The PRUs are used to generate step/direction pulses at (potentially) high speed, running simple code in a short loop (typically 1-10 uS), which is not possible on the ARM. Even with Xenomai, IRQ latency is on the order of 20-60 uS for the ARM, so it just can't run a task loop that fast. The PRUs don't have anything else to do, so they can happily make step/dir pulses with good timings while the ARM core handles the complicated not-so-time-critical stuff like motion planning, and the non-real time stuff like a user interface. On 3/31/2014 10:33 PM, Brad Hopper wrote: Charles any quick points or a link to something explaining what is the meaning of real time linux, especially in the context of having PRUs - I sort of had the sense that, for example in your machine kit image, the real time bits were being performed by the PRUs, so what is the reason for Xenomai? You have to run some OS of course, but if you have a dedicated subsystem that just comes up for air when it needs to inform the OS, why not just ?plain? linux? And if linux can run real time, why do you need the PRUs? maybe it's a matter of the scale of latency we're talking about. On Monday, March 31, 2014 6:08:27 PM UTC-4, Charles Steinkuehler wrote: On 3/31/2014 5:54 AM, Eren Basturk wrote: Hi All, I wonder that Is there any real time operating system to use on Beagle Bone Black? Could you give me some information about real time linux on Beagle Bone? TI has a list, but it doesn't include everything: http://www.ti.com/lsds/ti/tools-software/rtos.page ...conspicuously absent are the various non-commercial solutions. Is there something in particular you are wanting to run? -- Charles Steinkuehler cha...@steinkuehler.net javascript: -- Charles Steinkuehler char...@steinkuehler.net -- 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[beagleboard] Which Real Time Operating Systems Can I run on Beagle Bone Black?
Hi All, I wonder that Is there any real time operating system to use on Beagle Bone Black? Could you give me some information about real time linux on Beagle Bone? Thanks in Advance -- 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] Which Real Time Operating Systems Can I run on Beagle Bone Black?
On 3/31/2014 5:54 AM, Eren Basturk wrote: Hi All, I wonder that Is there any real time operating system to use on Beagle Bone Black? Could you give me some information about real time linux on Beagle Bone? TI has a list, but it doesn't include everything: http://www.ti.com/lsds/ti/tools-software/rtos.page ...conspicuously absent are the various non-commercial solutions. Is there something in particular you are wanting to run? -- Charles Steinkuehler char...@steinkuehler.net -- 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [beagleboard] Which Real Time Operating Systems Can I run on Beagle Bone Black?
Charles any quick points or a link to something explaining what is the meaning of real time linux, especially in the context of having PRUs - I sort of had the sense that, for example in your machine kit image, the real time bits were being performed by the PRUs, so what is the reason for Xenomai? You have to run some OS of course, but if you have a dedicated subsystem that just comes up for air when it needs to inform the OS, why not just ?plain? linux? And if linux can run real time, why do you need the PRUs? maybe it's a matter of the scale of latency we're talking about. On Monday, March 31, 2014 6:08:27 PM UTC-4, Charles Steinkuehler wrote: On 3/31/2014 5:54 AM, Eren Basturk wrote: Hi All, I wonder that Is there any real time operating system to use on Beagle Bone Black? Could you give me some information about real time linux on Beagle Bone? TI has a list, but it doesn't include everything: http://www.ti.com/lsds/ti/tools-software/rtos.page ...conspicuously absent are the various non-commercial solutions. Is there something in particular you are wanting to run? -- Charles Steinkuehler cha...@steinkuehler.net javascript: -- 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
