What has been coming through loud and clear is the "GPIO Settings" (the little box at the bottom of the images in the previous post). Let's talk about them.
I've done a lot of electrical engineering in my time with digital circuits, so I'm thinking of setting bits 3-7 how you would set up your GPIO on a microcontroller which would basically be bare-bones, fast with pull-downs (this is how a PIC is set up). You can have them float but then you would have to anchor them high or low externally, so let's just pull them down. A good conservative choice for setting these bits is x0100xxx (expressed in binary here). So how the GPIO Settings works is you have to set your bits in such a way as to produce the effect you want. Every pin has a MODE (REMEMBER this word) that allows you to configure the pin how you want it (ie. switching over a given GPIO pin to a UART pin so now you have serial communications). That's what the big tables above are for, they list all seven modes for each pin which value is put in bits 0-2. For example, if you wanted to set these bits to MODE 4 your byte would be 00100010 (in binary). On Thursday, March 9, 2017 at 5:17:59 AM UTC-7, woody stanford wrote: > > OK, I want to get to the bottom of this whole GPIO issue on the BBB, so > I'm opening up this thread as a "documenter" whereby which I can take notes > based on my research into how you consistently, stably and SOLIDLY > programatically access the GPIO pins on a BBB. I've already done a lot of > the footwork so I'm not entirely unknowledgeable, but I want to get to the > heart of this issue and solve the mental block people have with this. A > private hope. > > Either way, probably a good mess of processed links, articles and > information where you can start. > -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/cd71e879-07d3-4a1d-a350-30ede3c0de54%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
