On Friday, February 26, 2016 at 2:55:21 PM UTC-6, RobertCNelson wrote: > > > I'm having a lot of confusion as to what various dtb files do. > Offhand, > > I've no idea which ones would "force a "white" > > *.dtb on a black". > > In /boot/uEnv.txt if you manually set: > > dtb=am335x-bone.dtb > > Then boot on the Black with an microSD inserted, you'd fry the hdmi > chip ins a few reboots... >
This is very good to know, but I'm still in the dark about why I'd ever consider setting dtb=am335x-bone.dtb > What about: > > Suggested packages: > > linux-firmware-image-4.1.18-ti-r49 > > > > Should I install it? > > Nah, nothing in that is useful, just a few generic firmware blobs that > always get built by default... > > Thanks, usually I'm not paying enough attention to notice these "suggested" packages as the upgrade proceeds, this one I saw and thought I'd ask about. > I'm having trouble with the BB-UART1 overlay (I started another thread > with > > the details) so I'm trying the latest kernel and overlays in lieu of any > > suggestions yet from that thread. > > In that thread you were using "cape-universal" & BB-UART1.. > > Pick "one"... > > With cape-universal, you can set the usart pins to "usart".. no need > for the additional BB-UART1 > > root@beaglebone:~# config-pin -l P9.24 > default gpio gpio_pu gpio_pd uart can i2c pruin > > root@beaglebone:~# config-pin -l P9.26 > default gpio gpio_pu gpio_pd uart can i2c pruin > > root@beaglebone:~# config-pin P9.24 uart > > root@beaglebone:~# config-pin P9.26 uart > > and now /dev/ttyS1 should be working as a usart ;) > Bingo the minicom loopback test now works along with my application, almost too easy, I was reading up on config-pin yesterday but got confused and thought it couldn't be that simple :) I"m not sure I'll need rts/ctr but I see uart1 rts/cts on P9 19&20 are "not modifyable", guess they are now hardwired to /dev/i2c-2 in the kernel which I'm sure many people buying Beaglebones would prefer over a default interface to obsolete serial port equipment needing rts/cts hardware handshaking. Y'all have been making really great progress behind the scenes, but the details aren't getting out to where they can be easily found. While config-pin may not be the most efficient way, it takes a lot less effort than trying to learn how to write or modify an overlay! One, hopefully last, question about the boot up timing, if I wrote a script with a list of config-pin commands to setup what I need, could I run it with a root crontab @reboot? or would it be safer to run it via system() when my code is initializing the gpio via /sys/class/ file writes? Thanks again for all your help. --wally. > Regards, > > -- > Robert Nelson > https://rcn-ee.com/ > -- 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.
