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--- computing:beaglebone [2018/07/12 23:18] – oemb1905
+++ computing:beaglebone [2019/04/06 20:14] – oemb1905
@@ Line 26: / Line 26: @@
 Now that the image has been turned into an installer, you may put the microSD card into the Beagle Bone (without power).
-If there is a fourth pin, usually red, do not use.  We only need input, output, and ground.
+On a typical serial to USB adapter, and almost all others, the colors are white (receive), green (transmit), black (ground), red (5V power).  Do not use the red cable unless you know what you are doing.  Otherwise, make sure that the adapter's transmit goes to the Beagle's receive, and the adapter's receive to the Beagle's transmit.  The diagram below shows the Beagle's perspective. From left to right, there are 6 pins, so it would be : nothing, white, green, nothing, nothing, black.  The adapter commonly has a name like ttyUSB0, therefore this command should do the trick:
-  sudo screen <devicename> 115200
+  sudo screen /dev/ttyUSB0 115200
-  sudo screen /dev/ttyUSB0 115200 [Example]
 {{:computing:b1.jpg?400|}}
-When working with serial connections such as the Beagle Bone Black, and otherwise, screen can be helpful.  You can leverage screen with ssh to tunnel to another host, and then pass a screen command to keep the commands you initiate persistent on the client you connected to.
+Once the Beagle Bone is set up, one can leverage the screen command with ssh to tunnel to another host, and then pass a screen command to keep the commands you initiate persistent on the client you connected to.  That syntax looks like this:
-  ssh -p ### -t user@host.com screen -DRO
+  ssh -p 222 -t user@host.com screen -DRO
-Using screen with usb to serial adapter
-  sudo screen /dev/ttyUSB0 115200
+Some other common speeds are 9600, 57600, 38400, 19200.  For the Beagle Bone black, I always use 115200.  These speeds are in baud.
+-- -- -- -- -- --
+This section below is from some revisions I wrote for Jason's beaglebone stripping tutorial ...
+==Clean Up Post-Install==
+  apt-get install screen deborphan ntp
+the new version has an ntp server
+be sure to fix /etc/network/interfaces before removing connman - uncomment the lines for DHCP for eth0, remove extraneous lines and the manual entry that comes stock with bbb ... then connect to the beaglebone with ssh and screen ...
+  ssh -t root@<x.x.x.x> screen -DRO
+  for i in udhcpd chromium-codecs-ffmpeg-extra connman lximage-qt lxmenu-data pcmanfm-qt qupzilla xserver-xorg-core "light*" chromium-browser nodejs "lxqt*" xserver-common "apache2*" bluez "xfonts*" "x11-*" "x11proto-*" build-essential alsa-utils; do apt-get -y purge $i; done
+After this command, the ssh session hung, and we could only access with screen at a different speed of 9600 ... but, as long as you took care of /etc/network/interfaces above, then a reboot (worst case) or waiting should bring it back up.
+  apt-get --purge autoremove
+  apt-get --purge remove `deborphan` OR [apt-get purge `deborphan`] OR [apt-get purge $(deborphan)]
+run deborphan a few times untill all is removed
+  apt update
+  apt dist-upgrade
+  apt clean
+edit /etc/issue.net to remove the goofy ssh splash
+  cd /var/log && rm lastlog && ln -s /dev/null lastlog
+  cd /etc/cron.daily && mv man-db man-db.disabled [if it exists]
+to find latest writes to disk: find / -mount -newermt 14:44:00 [to see what logs are post-updates, i.e., for limiting writes to eMMC]
+Verify /etc/fstab configuration, include noatime like this example
+  FROM FSTAB:
+  UUID=57e4a3f6-7951-40ae-ad25-b445959e1c30  /  ext4  noatime,errors=remount-ro  0  1
+  debugfs  /sys/kernel/debug  debugfs  defaults  0  0
+#if we use an external sdcard, we are less concerned with re-writes, so enable the logs on the sdcard (create directories for each location below, mountpoints, etc.)
+  UUID=eb885f2f-28a4-49a6-99c9-3f8b0b7a871d /sdcard ext4 noatime,nofail,errors=remount-ro  0  2
+  /sdcard/tmp           /tmp            none bind,nofail 0 0
+  /sdcard/var/log       /var/log        none bind,nofail 0 0
+  /sdcard/var/lib/mysql /var/lib/mysql  none bind,nofail 0 0
+  /sdcard/var/lib/cacti/ /var/lib/cacti none bind,nofail 0 0
+  /sdcard/var/lib/ntp    /var/lib/ntp   none bind,nofail 0 0
+End of Jason's stripping tutorial ...
+-- -- -- -- --
+This tutorial is a designated "Invariant Section" of the "Technotronic" section of Haack's Wiki as described on the [[https://jonathanhaack.com/dokuwiki/doku.php?id=start|Start Page]].  This does not include the sections quoted from Jason's tutorial.
-Some other common speeds are 9600, 57600, 38400, 19200
+ --- //[[netcmnd@jonathanhaack.com|oemb1905]] 2019/01/13 12:22//

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