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--- ofi:vscode-ev3 [2022/06/24 18:21]
Ivo Blöchliger created
+++ ofi:vscode-ev3 [2023/01/20 21:11]
Olaf Schnürer
@@ Line 1: / Line 1: @@
 ====== Native Python auf EV3 mit VSCode ======
   * https://education.lego.com/en-us/product-resources/mindstorms-ev3/teacher-resources/python-for-ev3
-  * SSH: user robot, pass maker
+  * SSH: user robot, password maker
     * hostnamectl set-hostname LEGO12
+    * WiFi-Daten in var/lib/connman
   * https://docs.pybricks.com/en/stable/
+  * Use ''dd'' with the ''conv=sparse'' option. It will seek instead of write. Exactly what we need ;-)
+Way better than stuff below (also, you could take the image and then zero is out while mounted as loopback, much quicker!)
+<code ruby>
+def cmd(c)
+  puts c
+  r = `#{c}`
+  return r
+end
+raise "Provide hostname (like LEGO01)" unless $ARGV[0]
+hostname = $ARGV[0]
+img = "lego01.img"
+cmd("losetup -Pf #{img}")
+dev = cmd("losetup -j #{img}").split(":")[0]
+p2 = dev+"p2"
+cmd("mkdir -p p2")
+cmd("mount #{p2} p2")
+puts "Writing hostname #{hostname} to image"
+cmd("echo #{hostname} > p2/etc/hostname")
+cmd("umount p2")
+cmd("losetup -d ${dev}")
+puts "Image is ready. Write it with"
+puts "dd if=#{img} of=/dev/sdXXXX status=progress bs=1M conv=sparse"
+</code>
+<code bash>
+# Get Info
+sudo fdisk -lu lego12.img
+Disk lego12.img: 14.84 GiB, 15931539456 bytes, 31116288 sectors
+Units: sectors of 1 * 512 = 512 bytes
+Sector size (logical/physical): 512 bytes / 512 bytes
+I/O size (minimum/optimal): 512 bytes / 512 bytes
+Disklabel type: dos
+Disk identifier: 0xf5e5f871
+Device      Boot  Start      End  Sectors  Size Id Type
+lego12.img1        8192   106495    98304   48M  b W95 FAT32
+lego12.img2      106496 31116287 31009792 14.8G 83 Linux
+# Mount Partition, -o Start*512, --sizelimit Sectors*512
+sudo losetup -o 54525952 -b 512 --sizelimit 15877013504 /dev/loop16 lego12.img
+# Check filesystem
+sudo e2fsck -f /dev/loop16
+# Resize filesystem
+sudo resize2fs /dev/loop16 3750000
+# Mount filesystem
+mount /dev/loop16 /mnt
+# Zero out disk
+dd if=/dev/zero of=zero.txt bs=1M status=progress
+# Truncate image (size obtained from target SD-Card with fdisk -lu /dev/sda)
+truncate -s 15634268160 lego12.img
+</code>