Reading and Writing firmware images to uSD card

There are a variety of tools out there to perform this task.

We recommend using Disk Imager which (de)compresses images on the fly and thus can save significant disk space and reduce file transfer times.

https://github.com/DynamicDevices/DiskImager

Eliminating delay when booting without ethernet cable attached

Break into the u-boot boot and change the default kernel boot arguments like so,

• power on
• press a key to break into u-boot. you'll get a '=>' prompt
• enter the following

=> setenv bootargs 'console=ttymxc0,115200 init=/init video=mxcfb0:dev=lcd,SEIKO-WVGA,if=RGB666,bpp=24 video=mxcfb1:off video=mxcfb2:off video=mxcfb3:off vmalloc=256M androidboot.console=ttymxc0 consoleblank=0 androidboot.hardware=freescale cma=384M ip=none'

=> saveenv

=> reset

This will add 'ip=none' to the kernel boot arguments which will prevent the kernel delaying whilst it waits for DHCP to obtain an IP address.

I've checked that (a) this eliminates the delay and (b) the IP address is subsequently picked up when I insert the cable.

Prevent Android turning screen off

It is possible to turn the screen on when it goes off with

input keyevent 26

To ensure display stays on go to Settings->Developer Settings and select Stay Awake

Turn off Notification bar

TBD - This can be achieved by running an app full-screen but it would be useful to know how to disable this in the build

Changing the U-Boot splash screen

The splash screen needs to be in an 800x480x32 bit BMP format.

Not all graphics editing tools support saving in 32-bit format but this tool converts PNG format to 32-bit BMP

https://pngtobmp32.codeplex.com/

Note that the image needs to be flipped vertically, but not horizontally.

The image currently needs to be smaller than circa 15MB or it will overwrite the following partition on the uSD card. We have been using images around the 8MB mark with success.

To write the splash image to your Geneva Android uSD card use

$ sudo dd if=logo.bmp of=/dev/sdX bs=1 seek=1048576 skip=54

Where logo.bmp is your splash image and /dev/sdX is the device name of your uSD card. This can be retrieved after inserting the uSD card with dmesg | grep sd. Make sure you don't overwrite your development box file-system!

Changing the Android boot animation

Use this walkthrough to prepare a bootanimation.zip file with the appropriate format

https://community.nxp.com/docs/DOC-330208

There is a useful online tool to convert GIF animations to PNG frames here

https://ezgif.com/split

NB. There are also other EzGIF online tools there to generate and modify animations

Connect to the device via USB and use adb to remount the file-system read/write

adb shell mount -o rw,remount /system;

Next copy the file across and flush the file-system

adb push bootanimation.zip /system/media/bootanimation.zip;

adb shell sync;

Reboot the board