Chromebook Acer C720P getting Google Play Store with Chrome OS 65+ recovery from USB.

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Hnk1

Senior Member
Dec 23, 2012
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Moto G6
Does the method one by @Hnk1 in
https://forum.xda-developers.com/showpost.php?p=78806350&postcount=163

still work?
I tried ATB 78 special build with candy 78 recovery bin for my dell 3120 and while I can boot from the resulting USB. I do not see any Play Store in the launcher/ settings.
I noticed in method one in the above link
Code:
sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.B -f
sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.A -f
Are we supposed to copy vmlinuz.B to to both .B and .A or does the second line have a typo? I did use the commands exactly as mentioned in Method One.

Hi mate
The method one is for an old version of cyan c720P which resulted in playstore. We did not try other versions after it as google patched the method and it did not result in playstore anymore.

I think you will be more successful if you try method 2.
The last I used was cyan and eve 76 with fyde 7.1 which resulted in working playstore on cyan and I think also on dell 3120 . However, there was a sound bug which we could not solve. So we thought about using a USB audio jack which made the sound work as well.

I had success with dell 3120 on older builds as well like 70 of eve and cyan with fyde 5.3 or so.
The issue was still the sound!

If you need any help, let me know!
All the best
 
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cbay

Senior Member
Nov 1, 2007
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Hi mate

I think you will be more successful if you try method 2.
The last I used was cyan and eve 76 with fyde 7.1 which resulted in working playstore on cyan and I think also on dell 3120 . However, there was a sound bug which we could not solve. So we thought about using a USB audio jack which made the sound work as well.

I had success with dell 3120 on older builds as well like 70 of eve and cyan with fyde 5.3 or so.
The issue was still the sound!

Thanks for the reply.
I will try fyde 7.1 with cyan/eve 76. Can you confirm that it is eve 76 and not caroline 76 with cyan ? I thought you needed caroline for the TPM stuff. Or is that not needed on chromebooks.
Also, is it possible to leave it on a USB drive and not write to SSD? Do I need to adjust USB partition sizes using gparted for that?
 
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Hnk1

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Dec 23, 2012
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Moto G6
Thanks for the reply.
I will try fyde 7.1 with cyan/eve 76. Can you confirm that it is eve 76 and not caroline 76 with cyan ? I thought you needed caroline for the TPM stuff. Or is that not needed on chromebooks.
Also, is it possible to leave it on a USB drive and not write to SSD? Do I need to adjust USB partition sizes using gparted for that?

Hi

You are right.
It's Caroline !

I have cooked one for you. It's fyde72 with cyan nocturne and caroline all 76.

https://mega.nz/#!X9kjlKjJ!oo3hD02HEcxFoRAdMo4V_-gemNvRHJYsINPsS6uB0rE

Everything works except the audio on baytrail. Everything works for me on a haswell.

You can just dd it to usb if using Linux or use something like an IMG writer.

If you are on custom firmware and not on chromeos official like mrchrombox (and screw removed from your device), you can easily boot it up.

SSD or usb is your personal choice. I prefer it on my SSD. You can dd it to your hard disk after you are happy with it on a usb.

As said before, for sound just read some posts before. Can't make it run out of the box unfortunately.

All the best
 
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cbay

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Nov 1, 2007
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Thanks, will give it a shot.
I am not as much concerned about audio, don't need it for my main use :)
 
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Hnk1

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Dec 23, 2012
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Moto G6
Thanks, will give it a shot.
I am not as much concerned about audio, don't need it for my main use :)

I'll suggest try galliumOS as well.
I have moved away from chromeos and am using gallium on all devices.

It might be a bit difficult transition for you if you have never used Linux before, but the possibilities are limitless.

It's more stable and more versatile in my opinion. But in the end, whatever suits you the best !
I am only suggesting so you can look into all the options available.
 
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cbay

Senior Member
Nov 1, 2007
148
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Hi

You are right.
It's Caroline !

I have cooked one for you. It's fyde72 with cyan nocturne and caroline all 76.

https://mega.nz/#!X9kjlKjJ!oo3hD02HEcxFoRAdMo4V_-gemNvRHJYsINPsS6uB0rE

Everything works except the audio on baytrail. Everything works for me on a haswell.

You can just dd it to usb if using Linux or use something like an IMG writer.
Looks like link is to a directory (zipped) and not an IMG file. Don't I need an IMG file to put things in the right places
in for dd or etcher?

Also does fydeos need some kind of SMS/ FydeOS account to activate ?

And what is cyan nocturne ? Some kind of a mix? Do you have a link for it? I can't find it on
https://cros-updates-serving.appspot.com

I need the PlayStore, I don't think GalliumOS has it :)
 

cbay

Senior Member
Nov 1, 2007
148
21
Looks like link is to a directory (zipped) and not an IMG file.

OK the link seems to be pointing to an IMG file now.

I was able to put it on an USB, and boot. Mostly working, some problems faced

1. Play Store blinks a few times and crashes a lot (fix: enable Night Light on, as found on xda elsewhere).
2. Purschased apps did not show up as purchased. (fix: clear data and cache of the play store app, reboot).
3. 2GB space for APPs only. Low space warnings immediate. (fix: got into gparted and increased size of sdx3 as per project croissant github page and sdx1 to whatever was unallocated on my 64GB drive)
3. Touchpad and clicking not as good (I am running off usb)
4. At least one of my play store apps which uses wifi is having connectivity issues. This might be a chrome OS 76 bug. I guess I will have to try later versions of fyde/cyan/caroline.
 

nabil2000

Senior Member
Sep 12, 2005
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London
Chrome OS R80 - ATB 76, 80 /notes

I am rather inactive on this because of health issues (not coronavirus thankfully, yet)...

tested cyan & eve 80 on some devices...
eve 80 with chromefy no longer works for Acer CB C720P
cyan 80 works for all my devices, but no netflix for some
cyan 76 gives a working netflix as per the previous post.

Clearly Google does cripple iterations to disallow use.

Chromefy is on the way out it seems. No netflix using chromefy.

The method described in post #1 gives better outcomes for Acer CB C720P which is very similar to Acer CB R11 in hardware,
so using original ROOT-A partition & original 3.18 kernel helps for compatibility up to Chrome OS R80 so far.

Not much, but I thought I'll post this.

Addendum - FydeOS 9.2 with chromefy cyan 76 caroline 76 yields a good Android 7.1.1 with Netflix working as per the link above, also Linux VM good & Play Store good.
The problem is chromefy does not work well with Android 8 (Chrome OS R80 & above).
 
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    SOME NOTES, BACKGROUND and BASICS
    I only have made instructions more user friendly and writing my experience to help the community as when I started, it took me more than a week to get everything sorted out although I am quite familiar with chromebook and android. I have put links within text (orange colour) to make links more user friendly and this guide neater.

    I have intended to write this guide so that not only C720P users can benefit from it but also for other devices which lack android / linux support on their chromeboks. However, non chromebook users can benefit from it as well by using the second method or following Project Croissant.

    There are essentially two methods/ hacks which work with C720P which I know. All credits to @nabil2000 and Project Croissant @alesimula to make it possible.


    The method one is intended for chromebooks only whereas method two is intended to work on all devices and you can check the link mentioned in the name below.

    The first method was found by @nabil2000. In essence this method simply takes your chromebook image/ custom chromeos as base and uses another chromebook bin to overwrite the files, adding new ones and making it possible for old devices without android or linux support to run google play store and crostini.

    The second method works beyond chromebooks and can run on to almost any device which can be booted via a USB. There is a separate thread for it Project Croissant Link. However, I will also mention in easy steps how I used chromefy (Project Croissant).

    PRE REQUISITES FOR BOTH METHODS
    1. Chromebook running developer mode
    Turn it off and then press Esc+ Refresh+Power
    Ctrl+D to disable chromeos verification off
    This will reset your device so backup everything in advance.

    2. Enabling USB boot + Legacy Boot
    In your Chromebook, Open crouton (ctrl+alt+T)
    Type
    Code:
    Shell 
    
    sudo crossystem dev_boot_usb=1 dev_boot_legacy=1
    
    sudo crossystem dev_boot_usb=1
    Restart and this will enable usb boot

    METHOD 1


    METHOD 1 BASICS USEFUL FOR OTHER CHROMEBOOK USERS
    So the trick is to choose an IMG which supports your device hardware drivers, that's why special builds on ATB are preferred than vanilla ones, while FydeOS 5.3.1 also has a very wide range of driver support.

    Once you have choosen the IMG file, look for a BIN file which has GOOGLE PLAY STORE SUPPORT if you are looking for that, or Google Play Store and Linux if you are looking for both.

    So if you have a Dell 3120 which does not have both, look for a device which has google play store and Crostini and is very similar to Dell 3120 and choose that BIN. However, strangely EVE CAROLINE have more success rate than other builds.
    Another thing note mentioning is that suppose if you are using IMG base as 70, even using BIN file of 71 and 69 yields some great results. However, i think that using all three of same version might yield best results (i had similar success with different versions but YMMV)

    You just need to follow the same method for other devices and you only need to change bin file names and location (sdb sdc etc) in the script after you have chosen IMG and BIN files as close as possible for your devices.

    C720 METHOD
    Requirements

    1. A custom IMG (fyde /ATB/ your chromebook as base)
    2. A software like rufus/windows image write to write that image to a usb
    3. 1 or 2 USBs , 16gb are enough and for older versions even 8 gb is enough
    4. BIN file
    [/LIST]

    STEPS
    1. Write IMG of your choice to a USB ( ATB version 55 Special ) Download CYAN.bin
    2. Place the cyan.bin in your chromebook download folder or you can use a separate usb. I prefer it in chromebook download folder
    Ctrl+Alt+ T and type
    Code:
    shell
    move to your download folder using crouton by
    Code:
    cd home/chronos/user/Downloads     where D is case sensitive
    once you are there, check if your file is in the same folder. This will show your bin file name.
    Code:
    ls

    3.Type the following commands[/B]

    if you rename your file, make sure to rename it in the following command line as well. In my case it is chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin
    Also, make sure your name your usb sdb accordingly. The last command will take some time so be patient.

    Code:
    rootfs_start="`cgpt show -i 3 -n -b -q chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin`"
    
    rootfs_size="`cgpt show -i 3 -n -s -q chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin`"
    
    mkdir chrome_efi_mount
    
    sudo mount /dev/sdb12 chrome_efi_mount -t vfat
    
    mkdir chromium_efi_mount
    
    sudo mount -ro loop,offset=$((`cgpt show -i 12 -n -b -q chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin`*512)) chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin chromium_efi_mount
    
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.B -f
    
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.A -f
    
    sudo umount chrome_efi_mount
    
    sudo umount chromium_efi_mount
    
    sudo dd if=chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin of=/dev/sdb3 bs=512 skip=$rootfs_start count=$rootfs_size

    Once everything is done, turn off your PC and use ctrl U to boot from the USB. If everything working and all drivers are working well for your device, you can think of even writing your USB to your SSD. Intructions are after method 2


    METHOD 2
    Requirements
    1.Fyde 5.3.img
    2.Caroline 71.bin
    3.Cyan 71.bin
    4.Chromefy.sh
    5.Chromebook running developer mode which has usb boot enabled + legacy. Instructions above
    6. A live Linux usb. I prefer Ubuntu . You can use 8gb usb for this.

    Remember , You'll need at least 16gb usb for this to work on C720. I suggest use a good usb like sandisk extreme 16gb. I had two Kingston D50 3.0 but after few writes on them, they were dead. (Were easily claimed under warranty)
    However, an old SanDisk 2.0 cruzer blade and 16gb Kingston s9 2.0 survived many writes. So I suggest that get a usb which is 3.0 as it'll take less time to write and boot.

    STEPS
    1.Put all of above in a usb (fyde Caroline Cyan and chromefy) and connect it to your c720 running developer mode.
    2. Ctrl+Alt+T and you will be into crouton
    3. Type the following
    Code:
    shell
    sudo  bash  chromefy.sh  Fyde53.img  cyan71.bin  caroline71.bin
    It will start a script and may take up to 30 minutes. Answer N when prompted in the end. This will write all changes from bin files to your IMG.

    4.Once it is done, copy Fyde53 (or whatever the name was of your IMG) from USB and using either RUFUS / WINDOWS IMAGE BURNER to burn it on a USB having at least 16gb space.
    5. Once you have it burnt on a USB , boot with it by pressing ctrl+u
    6. Check if everything is working out and check playstore and everything is to your liking before you can think of writing it to your SSD.

    You'll notice that in your USB from which you are booting, it doesn't show the actual size of the disk.
    I suggest ignore it for now and you may write chromeos from your usb to your SSD.

    WRITING TO YOUR SSD FROM A WORKING USB
    Make sure you boot from the usb while trying to do this.

    1. In crouton , ctrl alt+t, first see the partitions by
    Code:
    Shell
    Lsblk
    2. Check which is sda and which is sdb etc . Usually SSD is sda while usb could be sdb or sdc . Make sure you check well.
    3.Next , check if your SSD partition size is larger than your usb. This is important because if the size is not same or less than usb size, it may end with errors. In my case, my usb was 28.2gb and my SSD was 29.2Gb. in your case, if your SSD actual size is 15.0Gb , make sure your usb is no larger than 15. Even 14.9 is fine else it may end up with errors.
    4. Type this command which will start writing from usb to ssd
    Code:
    sudo dd if=/dev/sdb of=/dev/sda bs=4MB
    This will end in few minutes. Do NOT STOP IN THE MIDDLE OR SHUT DOWN your PC while this is happening because it can potentially damage your SSD and you may need to buy a new one.

    5.Once this is done, you be running chromeos using ctrl +D from SSD.

    Now the issue of internal memory needs to be sorted.

    I used different Linux flavours (latest even ) to resize ssd partitions. You just need to resize your state partition to maximum size by using Linux gparted live usb. However, there is a very good chance you'll end up loosing attributes making your SSD non bootable. Thus you'll need to add the attributes back to your partitions by booting chromeos from the usb. I suggest before doing this, make sure you try it on a USB to see you can make it bootable again after resizing.

    To check your attributes, after shell in Chromebook crouton or in Linux if cgpt is installed,

    Code:
    cgpt show -d /dev/sda
    where sda is your ssd
    Kern-A will have attributes before resizing your disk and after that, they may be lost so you'll need to add by

    Code:
    cgpt add -i 1 -S 1 -T 5 -P 10 -l KERN-A /dev/sda2
    Where sda2 refers to kernel A partition when using cgpt show command.

    Once done , recheck and see that successful has 1 attribute. If yes, your SSD can boot on its own


    Reboot to check

    @nygmam

    On mrchromebox, you can have everything working with android 9, camera migration, google assistant and linux
    Steps here
    4
    Does Camd64OS_R55-8777.0-Special.7z already contain the chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin recovery, or do I still need to use the script in the original post to add it to sdb3? if not, why not to include it there in the first place? Or is this allows to inject recovery for different devices? What is in sdb3 of the 7z by default?

    ---------- Post added at 11:50 AM ---------- Previous post was at 11:01 AM ----------

    Today I got my first Chromebook - grabbed Acer C720 from eBay. I have 0 experience with Chrome os so had to figure few things out. Here is what I did to get google play store working on my c720 with the touchscreen. All the credit is to the nabil2000. I just collected all he said in one post. Please correct me if i got things wrong:
    1) Download and install win32diskimager-1.0.0-install.exe
    https://ayera.dl.sourceforge.net/project/win32diskimager/Archive/win32diskimager-1.0.0-install.exe

    2) Download extract and write to USB stick:
    Camd64OS_R55-8777.0-Special.7z
    https://www.dropbox.com/s/kebu46foi6quu96/Camd64OS_R55-8777.0-Special.7z?dl=0
    Use 7zip to extract IMG file from the downloaded file.
    Use Win32 Image Writer, then select the IMG file and select the USB device from the menu.
    Click on “Write”.

    3) Download and extract:
    chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin.zip
    https://dl.google.com/dl/edgedl/chr....0_cyan_recovery_stable-channel_mp-v3.bin.zip
    Also, @nabil2000 says you can use this one now:
    https://dl.google.com/dl/edgedl/chr....0_cyan_recovery_stable-channel_mp-v3.bin.zip

    4a) on ChromeOS
    press ctrl + alt + T and this brings you to what's called the crosh shell (command prompt or terminal) on a Chromebook. It'll now launch in a separate tab of the Chrome browser. Once the crosh shell has launched, you'll type “shell” to get to the root Linux shell from within your Chrome Browser

    CTRL-C to copy and CTRL-Shift-V to paste into the terminal

    4b) On Ubuntu machine:
    sudo apt-get install cgpt

    5) Create the script file:
    vi /tmp/myscript.sh
    # Get rid of the space in the first line in "stable" - no idea why xda forum injects a space there:
    image_file=chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin
    or the line below ,depending on which one you got in step 3
    image_file=chromeos_10575.58.0_cyan_recovery_stable-channel_mp-v3.bin
    rootfs_start="`cgpt show -i 3 -n -b -q $image_file`"
    rootfs_size="`cgpt show -i 3 -n -s -q $image_file`"
    mkdir chrome_efi_mount
    sudo mount /dev/sdb12 chrome_efi_mount -t vfat
    mkdir chromium_efi_mount
    sudo mount -ro loop,offset=$((`cgpt show -i 12 -n -b -q $image_file`*512)) $image_file chromium_efi_mount
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.B -f
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.A -f
    sudo umount chrome_efi_mount
    sudo umount chromium_efi_mount
    sudo dd if=$image_file of=/dev/sdb3 bs=512 skip=$rootfs_start count=$rootfs_size

    6) Copy .bin file to the same folder as a script
    At this point I assume your recovery .bin file should be located in the same folder as the script
    cp /media/samba_share/Downloads/c720/*.bin .
    7) verify that your usb stick is indeed /dev/sdb using dmesg

    8) run the script - on ubuntu I used
    bash -x myscript.sh

    9) to boot from USB you probably need to follow steps 1&3 (not sure if you need step 2) from here http://www.fascinatingcaptain.com/blog/dual-boot-chrome-os-and-linux/
    from the shell:
    sudo crossystem dev_boot_usb=1 dev_boot_legacy=1
    sudo enable_dev_usb_boot

    my system already came shipped with developers mode on, so I have not had to do step 1

    10)Boot from USB stick
    Unmount and remove that flash drive and insert it into one of your Chromebooks USB ports. Boot the device and then, at the startup screen, press Ctrl+l to boot from the legacy BIOS. When prompted, hit Esc to enter the boot menu and select 1 for the USB drive

    At that point my Chromebook booted and I have google play store. Everything is pretty slow, but I think this is due to the old and slow USB stick. I will now buy a faster low profile one. IS my USB stick now my storage. I have very little storage (about 3GB) after booting from USB. How can I expand it if I have a 32 GB stick? Any recommendations on the USB stick to use?

    >There's a more recent ROM (v66) that can be used to load Google Chrome OS with Play Store on USB of hybrid tablet Acer Iconia W700
    Does this also apply to c720?
    3
    Hi mate
    I have been following your updates for a while. Thanks a lot mate for updates and all your work.

    I was wondering, what is the best combo till now for c720P in which i can use google play and crostini ?
    I have managed to run play store from usb from your guide and want to have it on hard drive. What are my options ?

    Thanks alot

    The best combo so far for Acer CB C720P is FydeOS 5.3 with cyan R70 caroline R70 - you get everything working... but no google assistant as this is R71, which is not yet released for cyan - Acer CB R11 (cyan) is closest match to C720P.

    I never install to internal SSD, but if I wanted to, I will boot to a Linux live USB (ubuntu 18.04) and do:
    $ sudo dd if=/dev/sdb of=/dev/sda bs=4M
    with /dev/sda the internal SSD & /dev/sdb the usb stick that holds a working Chrome OS I chromefied to.

    PS & NB - make sure you saved a recovery USB for your CB in case you bork it...
    Also if you did not know, this is how identify disk drives /dev/sdx (x=a,b,c...)
    $sudo fdisk -l
    3
    [CHROMEFY] Install official Chrome OS w/ Android & crostini for Acer Chromebook C720P

    1. You need two USB sticks with arnoldthebat Chromiusm OS enhanced R69 special build - get it here:
    https://arnoldthebat.co.uk/wordpress/chromiumos-special-builds/
    Using windisk imager, image the 2 sticks with the Chromium OS.
    One stick (with Chromium OS r69) will be to boot to from USB, the other stick (or SSD) will be to install Chrome OS to.

    N.B. The target install partition to hold Chrome OS ROOT-A /dev/sdc3 in my case, needs to be resized to at least 4GB (from 2 GB) -
    I used gparted gui from a Ubuntu livecd to resize it, expand it by 2048MB,
    this requires to rezise/move the /dev/sdc1 partition to the right by 2048MB, then resize /dev/sdc3 by expanding it by 2048MB.

    2. Boot up to the installation/configuration stick (from above) & download the chromefy.sh script from
    https://github.com/imperador/chromefy/releases/tag/v1.1
    to a folder in~/Downloads
    (specifics left to you)

    3. Download from Google repository these two recovery images
    fizz
    chromeos_10895.78.0_fizz_recovery_stable-channel_mp-v8.bin.zip
    caroline
    chromeos_10895.78.0_caroline_recovery_stable-channel_mp.bin.zip

    url addresses in first post of this thread...

    unzip both bin images to a folder in ~/Downloads
    (specifics left to you)

    4. Determine which is the location of the second USB stick you want as target (it has the second Chromium OS you imaged earlier)
    In my case it is /dev/sdc
    (/dev/sda is the internal, /dev/sdb is the Chromium OS you booted into & are working from)

    5. from a shell (ctlt-alt-t)
    $ shell
    $ cd ~/Downloads
    $ sudo df # (or sudo fdisk -l) to determine disk target
    $ sudo bash chromefy.sh /dev/sdc3 chromeos_10895.78.0_fizz_recovery_stable-channel_mp-v8.bin chromeos_10895.78.0_caroline_recovery_stable-channel_mp.bin

    that's it - it will do its thing, then ask you to reboot...
    remove the 1st usb stick, replace it with the 2nd usb stick, boot from it
    & you have, hopefully, a fully working Chrome OS with Linux Kernel 4.14, Android & crostini enabled...

    ack & greets, respect to anoldthebat & the chromefy team for making this possible...

    small caveat - you cannot root android in this setup as trying to make the system r/w wrecks the setup - welcome to solve this ;)

    NB & PS -
    It might be a good idea to use the combo cyan / caroline first in 5) to start with to make sure to avoid the blank screen described below for Acer Chromebook C720P...
    3
    Does Camd64OS_R55-8777.0-Special.7z already contain the chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin recovery, or do I still need to use the script in the original post to add it to sdb3? if not, why not to include it there in the first place? Or is this allows to inject recovery for different devices? What is in sdb3 of the 7z by default?

    ---------- Post added at 11:50 AM ---------- Previous post was at 11:01 AM ----------

    Today I got my first Chromebook - grabbed Acer C720 from eBay. I have 0 experience with Chrome os so had to figure few things out. Here is what I did to get google play store working on my c720 with the touchscreen. All the credit is to the nabil2000. I just collected all he said in one post. Please correct me if i got things wrong:
    1) Download and install win32diskimager-1.0.0-install.exe
    https://ayera.dl.sourceforge.net/project/win32diskimager/Archive/win32diskimager-1.0.0-install.exe

    2) Download extract and write to USB stick:
    Camd64OS_R55-8777.0-Special.7z
    https://www.dropbox.com/s/kebu46foi6quu96/Camd64OS_R55-8777.0-Special.7z?dl=0
    Use 7zip to extract IMG file from the downloaded file.
    Use Win32 Image Writer, then select the IMG file and select the USB device from the menu.
    Click on “Write”.

    3) Download and extract:
    chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin.zip
    https://dl.google.com/dl/edgedl/chr....0_cyan_recovery_stable-channel_mp-v3.bin.zip

    4a) on chromeos
    press ctrl + alt + T and this brings you to what's called the crosh shell (command prompt or terminal) on a Chromebook. It'll now launch in a separate tab of the Chrome browser. Once the crosh shell has launched, you'll type “shell” to get to the root Linux shell from within your Chrome Browser

    CTRL-C to copy and CTRL-Shift-V to paste into terminal

    4b) On Ubuntu machine:
    sudo apt-get install cgpt

    5) Create the script file:
    vi /tmp/myscript.sh
    image_file=chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin
    rootfs_start="`cgpt show -i 3 -n -b -q $image_file`"
    rootfs_size="`cgpt show -i 3 -n -s -q $image_file`"
    mkdir chrome_efi_mount
    sudo mount /dev/sdb12 chrome_efi_mount -t vfat
    mkdir chromium_efi_mount
    sudo mount -ro loop,offset=$((`cgpt show -i 12 -n -b -q $image_file`*512)) $image_file chromium_efi_mount
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.B -f
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.A -f
    sudo umount chrome_efi_mount
    sudo umount chromium_efi_mount
    sudo dd if=$image_file of=/dev/sdb3 bs=512 skip=$rootfs_start count=$rootfs_size

    6) Copy .bin file to the same folder as a script
    At this point I assume your recovery .bin file should be located in the same folder as the script
    cp /media/samba_share/Downloads/c720/*.bin .
    7) verify that your usb stick is indeed /dev/sdb using dmesg

    8) run the script - on ubuntu I used
    bash -x myscript.sh

    9) to boot from USB you probably need to follow steps 1&3 (not sure if you need step 2) from here http://www.fascinatingcaptain.com/blog/dual-boot-chrome-os-and-linux/
    from the shell:
    sudo crossystem dev_boot_usb=1 dev_boot_legacy=1

    my system already came shipped with developers mode on, so i have not had to do step 1

    10)Boot from USB stick
    Unmount and remove that flash drive and insert it into one of your Chromebooks USB ports. Boot the device and then, at the startup screen, press Ctrl+l to boot from the legacy BIOS. When prompted, hit Esc to enter the boot menu and select 1 for the USB drive

    At that point my Chromebook booted and I have google play store. Everything is pretty slow, but I think this is due to the old and slow USB stick. I will now buy a faster low profile one. IS my USB stick now my storage. I have very little storage (about 3GB) after booting from USB. How can I expand it if I have a 32 GB stick? Any recomendations on the USB stick to use?

    >There's a more recent ROM (v66) that can be used to load Google Chrome OS with Play Store on USB of hybrid tablet Acer Iconia W700
    Does this also apply to c720 ?

    Steps 4B and 5 did not work for me using Ubuntu 18.04 64-bit to tweak the Chromium 64-bit thumb drive
    4B. Using Ubuntu 18.04 64-bit platform, install cgpt is slightly different:
    sudo apt install cgpt

    5. Using same Ubuntu 18.04 64-bit platform, I extracted/copied chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin into my login profile's Downloads folder.
    Then manually I ran terminal from there, "[email protected]:~Downloads$"
    rootfs_start="`cgpt show -i 3 -n -b -q chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin`"
    rootfs_size="`cgpt show -i 3 -n -s -q chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin`"
    mkdir chrome_efi_mount
    sudo mount /dev/sdb12 chrome_efi_mount -t vfat
    mkdir chromium_efi_mount
    ###below is one long line
    sudo mount -ro loop,offset=$((`cgpt show -i 12 -n -b -q chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin`*512)) chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin chromium_efi_mount
    ###End of one long line
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.B -f
    sudo cp chromium_efi_mount/syslinux/vmlinuz.B chrome_efi_mount/syslinux/vmlinuz.A -f
    sudo umount chrome_efi_mount
    sudo umount chromium_efi_mount
    sudo dd if=chromeos_10323.62.0_cyan_recovery_stable-channel_mp-v3.bin of=/dev/sdb3 bs=512 skip=$rootfs_start count=$rootfs_size

    Booted it up on C720P and logged in...BOOYAH! Google Play Store. So funny as I bought an R11 Cyan for this very purpose and now it's running on my ol' C720P. Giving the R11 to my wife. :)