Am 13.02.2018 um 12:05 schrieb Chris Johns: > >> On 13 Feb 2018, at 5:37 pm, Christian Mauderer >> <christian.maude...@embedded-brains.de> wrote: >> >>> Am 13.02.2018 um 00:34 schrieb Chris Johns: >>>> On 13/02/2018 00:39, Christian Mauderer wrote: >>>> These patches add various improvements for the atsam BSP and for the >>>> sc16is752 SPI UART controller. >>>> >>>> Regarding patch 1: Note that I have thought about an auto detection >>>> instead of the option. But I had a board where something responded to >>>> the oscillator so that I could initialize it despite the fact that no >>>> crystall has been connected. So I think an auto detection would be >>>> dangerous. >>> >>> I agree with this approach. >>> >>> Auto-detection is OK in systems with users however in embedded systems it is >>> dangerous. I have a rule, any auto-detection requires a system level module >>> that >>> audits the part of a system that has auto-detection and raises any >>> unexpected >>> differences as errors. Auto-detection can be hard to avoid in some systems, >>> ie >>> PC motherboards, PCI etc. >>> >>> I remember back in the mid-90s working on an important system with RAM size >>> detection where one of two static RAM chips had started to fail and the >>> system >>> adjusted assuming this was all the available memory so no one noticed until >>> many >>> many months into operation the application was reconfigured and it ran out >>> of >>> memory when it should not have. At the start of the project I had been >>> asked to >>> add the memory detection to handle different build variants of the >>> hardware. The >>> feature was disabled and I have not been a fan of it ever since. >>> >>> Chris >>> >> >> Hello Chris, >> >> thanks for the support for this approach. I mostly wanted to give a >> reason why I thought it would be necessary to add another option to the BSP. >> >> Any other remarks regarding the patches? Can I apply them? >> > > Yes, they look fine. I do not know the hardware so I assume that part is > fine. > > Chris >
Hello Chris, thanks for taking a look. I pushed the patches. Regards Christian -- -------------------------------------------- embedded brains GmbH Herr Christian Mauderer Dornierstr. 4 D-82178 Puchheim Germany email: christian.maude...@embedded-brains.de Phone: +49-89-18 94 741 - 18 Fax: +49-89-18 94 741 - 08 PGP: Public key available on request. Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG. _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
