On 7/31/2016 4:54 PM, John Kasunich wrote: > > I found the source on github, which included a commit from > January 2015, where Charles changed the pin numbering from > 1xx and 2xx to 8xx and 9xx. However, the Xylotex sample > configuration (as shipped in early 2016) is still using the 1xx > and 2xx pin numbering scheme. It looks like the Xylotex > config wasn't updated when the pin numbering was revised > (and it also looks like it hasn't been tested since early 2015, > since that change should have broken the config).
The 1xx/2xx and 8xx/9xx pin numbering are equivalent and can be used interchangeably. > I'm about 99.9% sure that I need to invoke the startup script > to deal with device trees and other hardware issues. But the > startup script is also totally undocumented. > > My plan was for this email chain to continue documenting > forward progress. However, I'm very frustrated by the lack of > documentation for BeagleBone specific code that has been > added to machinekit. I will continue trying to figure this out, > but I'm going to hit send in that hopes that someone can > help. Sorry about your issues. I'm 99.9% sure you're hitting an ARM SoC issue. On the ARM in general and the BBB specifically, the GPIO banks are not enabled at power-up. If you do not export a GPIO pin from a bank (and there are four unique GPIO banks for the BBB), it will not be powered on or have a clock routed to it, so any accesses to the physical address of the GPIO bank will cause a bus exception. You should load a device-tree overlay that enables the GPIO bank(s) you want to use prior to loading the hal_bb_gpio driver. The easiest way to do this is to load my "universal" overlay and then use the config-pin utility to set the GPIO pins to input, output, or a special function (PWM or encoder) as required. You are correct that this isn't really documented anywhere, and that needs to be corrected. At least I did finally manage to write a man page for the hal_pru_generic driver! (baby steps) :) -- Charles Steinkuehler [email protected] -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. Visit this group at https://groups.google.com/group/machinekit. For more options, visit https://groups.google.com/d/optout.
