14:23 <rcn-ee> zmatt: having a brain fart that maybe you can help with... Did you do something with crazy un-standard baud rates over the omap's usart... I swear you had a custom patch/script somewhere..

15:14 <Pieter> Hi, does anyone have advice on how to install ROS on a BB Blue, without it being oriented towards EduMIP? I'd like to use ROS since it has a few opensource tools I need such as OpenCV and SLAM algorithms I need to use in conjunction to a LiDAR. There are only a small amount of guides I've been able to find and almost none of them mention if the

15:14 <Pieter> PRUs will be working (I have motors I'd like to operate through the PRUs). I know I'll need to run off an SD card but a lot of images relating to ROS on Ubuntu have been removed (most recent I know of is 18.04 and I can't find the image)

15:25 <zmatt> rcn-ee: we have our serial console at 460800, but that's not too "crazy nonstandard" though, it's just 4*115200

15:27 <zmatt> rcn-ee: I don't recall if I ever upstreamed the u-boot patches to support that baudrate... I think I might have?

15:30 <zmatt> rcn-ee: this is that patch set: https://github.com/dutchanddutch/u-boot/commits/patch/v2018.03/uart

15:37 <rcn-ee> thanks zmatt, user is trying to configure it to 5787... i thought you had a patch for the kernel or userspace that allowed any frequency.. (not sure the hardware can even hit that number with the multiplers/dividers...)

15:56 <Pieter> Anyone able to help installing ROS?

16:00 <zmatt> rcn-ee: 5787 Hz ? o.O

16:03 <zmatt> rcn-ee: the hardware can do that just fine

16:05 <zmatt> rcn-ee: https://docs.google.com/spreadsheets/d/1L54wNj2Dkn6B98Z2sBqR7yq_qbOFiDDCR1M2F5dDaBM/edit?usp=sharing (the am335x uarts have an 48 MHz except the PRUSS UART which has a 192 MHz clock)

16:05 <zmatt> rcn-ee: I'm pretty sure there's a way to configure an arbitrary baudrate in linux

16:17 <zmatt> rcn-ee: I think it's just stty that's being sucky, py-serial seems to have no problem with it: https://pastebin.com/raw/1sPM6t92

16:19 <zmatt> hmm, py-serial never seems to report an error though

16:37 <zmatt> rcn-ee: it's a bit weird.. the linux kernel defines a struct termios that lacks explicit baudrates and a new struct termios2 that adds these: https://elixir.bootlin.com/linux/latest/source/include/uapi/asm-generic/termbits.h ... and each has an associated set of ioctls (TCGETS/TCSETS/TCSETSW/TCSETSF and TCGETS2/TCSETS2/TCSETSW2/TCSETSF2)

16:38 <zmatt> except powerpc which lacks termios2 and associated ioctls because termios already has the baudrate fields there: https://elixir.bootlin.com/linux/latest/source/arch/powerpc/include/uapi/asm/termbits.h

16:40 <zmatt> and glibc's struct termios does seem to include c_ispeed/c_ospeed except it looks like it just always uses the old kernel termios, discarding the explicit baudrate fields

16:40 <zmatt> forcing you to use the ioctls directly instead of tcgetattr()/tcsetattr()

16:45 <zmatt> (deep sigh)