ALARM Samsung Chromebook - Following guide

[Kausion]

Hello, Im trying to follow the installation guide but I run into problems when I reach step 6.

Replace the xxxxx string in the following command with that number to create the root partition:
cgpt add -i 3 -t data -b 106496 -s `expr xxxxx - 106496` -l Root /dev/sda

When I get to this point, I keep getting different errors depending on what I change up ( Never did anything like this before), what am I doing wrong? Ive followed it step by step so far.

$this->bbcode_second_pass_code('', ' localhost / # cgpt add -i 3 -t data -b 106496 -s 976773135 - 106496 -l Root /dev/sda
ERROR: cgpt add: Can't open -: No such file or directory

localhost / # cgpt add -i 3 -t data -b 106496 -s 976773135 106496 -l Root /dev/sda
ERROR: cgpt add: Can't open 106496: No such file or directory

localhost / # cgpt add -i 3 -t data -b 106496 -s '976773135 - 106496' -l Root /dev/sda
ERROR: cgpt add: invalid argument to -s: "976773135 - 106496"
')

[WarheadsSE]

Here's a hint. Do the math, plug in the result

Or, actually use the ` not ' and add the expr that is there.

[Kausion]

Got it. Didnt notice I was using the wrong symbol. Thank you. Will follow up if I run into another problem/succeed

[Kausion]

Everything went fine from their upto Step 15/16 -
Pressing Ctrl-U makes the screen studder and stays on the splash screen/U-Boot never starts. What did I do wrong now?

15. At the splash screen, instead of pressing Ctrl-D to go to CromeOS, press Ctrl-U to boot to the external drive.

16. You will see U-Boot start after a moment and start counting down from 3. Press any key at this time to interrupt the boot process and get a prompt that looks like:
SMDK5250 #

[raumzeit]

Sounds like the trouble I had in the beginning... You have to enable the Developer Switch as well as Developer mode BIOS, see also http://archlinuxarm.org/forum/viewtopic.php?f=9&t=5919#p34186

[WarheadsSE]

We added that to the instructions a while ago.

[Kausion]

Alright, I enabled the dev-bios. Same scenario though, Ctrl-U at spash causes screen studder/beep and nothing happens. I am using an external HD though and not a usb stick?

[WarheadsSE]

It might not be "spinning up" in time. Try it with a small USB stick to confirm.

[Kausion]

Indeed it did work on a stick. Unfortunately, its a 1gig stick haha. Dont suppose theirs a workaround for ext HDs not spinning in time?

[WarheadsSE]

Sadly, not really.