updated readme

README.md

@@ -18,16 +18,20 @@ Below are the steps required to set up a stock Jetson to use this code base:
 
 ### Cloning The CAS Lab Jetson Image
 
-To set up a new SD card using the image on the drive, follow the steps below. Instead of using a loopback device you can just use another SD from an already set up Jetson, in which case the loopback stuff can be skipped. Disclaimer, these commands are pretty dangerous if mistyped and the original contents of the SD will be deleted of course. Also this process needs to be done on a linux machine with a lot of free space.
+To set up a new SD card using the image on the drive, follow the steps below. Instead of using a loopback device you can just use another SD from an already set up Jetson, in which case the loopback stuff can be skipped. Disclaimer, these commands are pretty dangerous if mistyped and the original contents of the SD will be deleted of course. Also this process needs to be done on a linux machine with a lot of free space. The majority of these steps were taken from this one random forum [post](https://forums.developer.nvidia.com/t/shink-system-image-of-jetson-nano-for-smaller-size-sd-card/80522/16).
 
 * Prepare the image on a loopback device
   - Find the next free loopback device with `losetup -f`, this gives you something like `/dev/loop12`. We'll keep using `/dev/loop12` but yours may differ.
   - Link the loopback device with the image in question by `losetup /dev/loop12 path/to/neruda_backup.img`, the second argument being the CAS Lab Jetson image.
-  - Check out the partition table of the image `fdisk -l`
-  - TBD!
+  - Check out the partition table of the image `fdisk -l`, there should be 12 different partitions with the first taking the majority of space on the image. 12 here being the same as the loopback device is just a coincidence.
+  - After all the other steps are completed, remove the loopback device with `losetup -d /dev/loop12`
 
-
-  - Remove the loopback device with `losetup -d /dev/loop12`
+* Copy partition table to SD
+  - Open the loopback device (or SD card, if cloning an already set up card) with `gdisk /dev/loop12`
+  - Enter expert command mode with `x` (can use `?` to get commands)
+  - Select `copy partition table to new device` and type `/dev/loop12` in the prompt, this may throw warnings but they are likely to do with overwriting existing data
+  - Write changes to disk with `w` and `y` in the prompt, exit gdisk if no errors.
+  - Now we can copy the contents of each partition to the target drive, which we'll call `/dev/sdb` but yours may differ. Find target SD card with `fdisk -l` with and without the card plugged in. Run `dd if=/dev/loop12p1 of=/dev/sdb1` for each partition in `/dev/loop12` of which there are 12 (tedious as heck, sorry). The target SD card now should be a perfect clone of the source.
 
 ### UDEV Rules File
 
@@ -52,7 +56,7 @@ The hosts contents, to be placed in `/etc/hosts` is listed below
 192.168.1.102   plath
 192.168.1.24    plathHouse
 192.168.1.103   yeats # --> your hostname here, house denotes local home network
-192.168.1.198   yeatsHouse
+192.168.1.198   yeatsHouse # --> these house IPs are from a random home router, change if using
 
 # The following lines are desirable for IPv6 capable hosts
 ::1     ip6-localhost ip6-loopback
@@ -61,18 +65,21 @@ ff00::0 ip6-mcastprefix
 ff02::1 ip6-allnodes
 ff02::2 ip6-allrouters
 ```
-
 ---
 
 # Hardware Setup
 
 Procedure for drone-Jetson communication is found [here](https://developer.dji.com/onboard-sdk/documentation/development-workflow/hardware-setup.html) note details on Advanced Sensing as they are required to use drone cameras.
 
-
 # Debugging
 
 Why it doesn't work??
 
+* Check that the SD card is pushed all the way into the slot, this happens quite a lot
+* Try the SD card in a different Jetson to see if the Jetson is to blame
+* Check that the power LED on the board is turning green when plugged in
+* Wifi is likely not set up correctly after cloning (MAC address conflicts happen), plugging in an HDMI and keyboard can be helpful, rather than going headless
+
 ### Vehicle Activation Errors
 
 Check [here](https://forum.dji.com/thread-216529-1-1.html).