[Android Head-Units] Tuatara:
Huawei Modems - Android needs them to be in modem-only mode!

I'll say this again ... use a minimum of a 12V/1A supply, appropriate pin (very small), and it is centre-tip positive.

(NOTE: The actual power supply voltage CAN be lower and still work, because it is internally regulated down to 5V, but it should then be a CLEAN supply [i.e. no supply ripple, or cheap rectification stages in it]).

Using the USB OTG Port or the Host USB Port is not recommended, as these have BY DESIGN a 500mA limit, which will not be enough to run the Android box, the HDMI, and anything else plugged into any USB port. If you are running it in this way, you are exceeding the design specifications. Use the right plug for the job. Highly recommended - even if you discover that it does work the other way.

You're welcome. Unfortunately, while I believe it would be 100% safe (i.e. you can't brick your unit) performing the update from the stock ROM, I wouldn't recommend it. First, you will NOT get the benefit of the repartitioning I've done (more apps space, etc.). Secondly, I'm not certain if it would like the new partition layout in the ROM, and can flash it accordingly.

If you want to back up your current setting using ClockworkMod you can do that. Refer back a few posts of mine, and you will find instructions for flashing JUST the recovery.img partition, which will give you ClockworkMod. With that you can make a Nandroid Backup, and give the upgrade a try (I'd be curious to know if it works!).

If it fails, and the unit can not boot - then you will need to use the RKBatchTool (install drivers, etc.), and boot it into bootloader mode. To do this, there is a small silver 'pin hole' on the android unit. Hold this button down with a paperclip while you power up the unit VERY gently!!! It is a very soft 'click' you will feel. Let the unit boot. Nothing will appear on the HDMI, but the [1] will go "green" in RKBatchTool, and you can then [RESTORE] a new ROM. You really can never brick one of these units. It's wonderful. :)

---------- Post added at 11:07 AM ---------- Previous post was at 11:01 AM ----------

Modem only mode is required for Android to detect the modem. Android can not properly deal with a 'multi-function' device, with CD-ROM, USB Storage, and modem, as it is missing the mode switch operations normally applied by an OS.

Putting the E220 into modem-only mode is the correct procedure. Ensure that you've done this correctly.

Reference: http://www.techytalk.info/disable-virtual-cd-rom-drive-with-built-in-software-on-huawei-and-zte-gsm-modem-devices/

---------- Post added at 11:20 AM ---------- Previous post was at 11:07 AM ----------

I'm using an E1552, and have set it to modem-only mode. It works flawlessly, every time, connecting immediately on boot.

http://www.techytalk.info/disable-virtual-cd-rom-drive-with-built-in-software-on-huawei-and-zte-gsm-modem-devices/

Reboot with a full power off. That will cause the linux boot to rescan it properly and it should then be recognized.

I'm using it on the Host Port without issues (actually - through a 7 port USB hub - mbeat USB3.0+2.0 individually switchable).

I'm running 32GB USB key, Huawei 1552, 32Gb Sandisk Flash, Mouse, Keyboard, Vehichle Interface, and extra ports on it.

I'm keeping the USB OTG free for the MyGica PT360 - arriving soon!