Diagnostics & Development
Diagnostics & Development
I take no responsibility.............. DO IT ON YOUR OWN RISK!
This part of the thread will be dedicated to reading and diagnosing logs , and more advanced stuff for developers
most of the usb-related stuff are using kernel messages to let us know their status
to read kernel messages we can use
Android Debug Bridge ( or ADB )
the original protocol is used via USB , but we already use it to connect our usb devices so we need a different route
So , you should basically know 2 apps :
adbWireless enables a wireless ADB connection , just like USB so you can view logs on your PC
Android Terminal Emulator will let you use Android's built-in Linux command line shell right on the nook itself.
It doesn't matter what you choose , those are just 2 different ways to view the same thing - and you will know more by the end of this post
I'll try to make this post appeal to both the command-line and GUI guys
You can use the following on both CM7 & CM9
So , open your app of choice ( adbWireless / Terminal Emulator / Whatever ) and establish a connection ( shell ) if needed
First you should start with
Since we are dealing with kernel stuff , you need superuser permissions.
this command will give you root access till the end of the session.
If you see ‘#’ - you already got root access
If you see ‘$’ - type ’su’ to get root access.
Now that we got root permissions we have read&write access to the system
Here is a list of relevant commands and their actions
Code:
[B]logcat[/B] - view the internal log of the Android system
[B]dmesg[/B] - view the message buffer of the kernel
[B]cat /proc/kmsg[/B] - continuous dmesg ( to stop the log use ctrl+c )
[B]echo host > /sys/devices/platform/musb_hdrc/mode[/B] - usb host ON
[B]echo peripheral > /sys/devices/platform/musb_hdrc/mode[/B] - usb host OFF
[B]echo external > /sys/devices/platform/i2c_omap.1/i2c-1/1-0048/twl4030_usb/vbussrc[/B] - external vbus ON
[B]echo internal > /sys/devices/platform/i2c_omap.1/i2c-1/1-0048/twl4030_usb/vbussrc[/B] - external vbus OFF
[B]lsusb[/B] - list usb devices
[B]cat /proc/asound/cards[/B] - list audio devices
General :
Lumberjack - Log export and viewer
CommandCenter -
CM7 Support
USB HOST :
USB Host Viewer
USB Device Info
USB Host Diagnostics -
CM7 Support
Usb Host Controller -
CM7 Support
How To Diagnose Power Requirements ( 100mA limit )
As I stated earlier some devices require more than 100mA to become functional
in that case this can be easily spotted by looking at the logs ,
Enter cat /proc/kmsg on adb/terminal or watch dmesg log on lumberjack
Connect your usb device and look for the
RED line :
Code:
<6>usb 1-1: Product: U3 Cruzer Micro
<6>usb 1-1: Manufacturer: SanDisk
<6>usb 1-1: SerialNumber: 0572710F0A803B8A
<7>usb 1-1: uevent
<7>usb 1-1: usb_probe_device
[B][COLOR="Red"]<6>usb 1-1: rejected 1 configuration due to insufficient available bus power[/COLOR][/B]
<4>usb 1-1: no configuration chosen from 1 choice
If you see it that means you
need to connect an external power source ( hub for example )
Re-Mapping Input Buttons/Keys
Let's say you are using a full keyboard with Multimedia/Function keys or some kind of an HID device with buttons
And you want to map/re-map specific keys to do other functions in the system such as controlling volume , play/pause , go to home etc..
This is how you do it
- Install KeyEvent Display
- Connect your usb input device
- Press the key you want to re-map and look for its scancode ( key code )
Here you can see I pressed FN+Print Screen keys on my logitech keyboard , and found out the their scancode is 127
- Open your favorite file browser ( I use Root Explorer )
- Navigate to /system/usr/keylayout
- backup Generic.kl file!
- Edit Generic.kl , look for the keycode you found and change it's command
My original layout :
As you can see it's mapped as a menu key
Now let's say for example I wanted this combination to trigger default music app , all I need is to change the highlighted line to
If you see '#' in the start of the line , delete it to make the key active
If your keycode doesn't exist - you can add it in a new line ( make sure it doesn't exist before you create a new line )
- Save and Reboot! ( you must reboot for changes to take effect )
Since we are changing Generic.kl , almost every input device that is connected or present on the nook will be effected by the change
If at any step you find the hardware keys / keyboard not working properly - restore to your backup and reboot.
If you have more than 1 device with the same keycode and you need them to perform different actions you will have to create a specific key layout
More info can be found @
Key Layout Files
NOTE : This was tested on CM9 , I'm not sure this works on CM7 as well ( although probably not as generic.kl was introduced in HC )
Controlling USB Host & External VBus via Tasker
- Install "Locale Execute" plug-in from the Market
- In Tasker open "Tasks" and make a new one (e.g. "USB Host ON")
- Category: Plugin Action: Execute
- Give it a name on the label and push the edit button
- Insert the command
Code:
@! echo host > /sys/devices/platform/musb_hdrc/mode
- Apply
You can now test it , or use it in a profile of your choice.
Superuser App will ask for permission for *every single new command* you use in Locale Execute. No workaround.
Use these commands to control usb host & external vbus state
Code:
[B]@! echo host > /sys/devices/platform/musb_hdrc/mode[/B] - usb host ON
[B]@! echo peripheral > /sys/devices/platform/musb_hdrc/mode[/B] - usb host OFF
[B]@! echo external > /sys/devices/platform/i2c_omap.1/i2c-1/1-0048/twl4030_usb/vbussrc[/B] - external vbus ON
[B]@! echo internal > /sys/devices/platform/i2c_omap.1/i2c-1/1-0048/twl4030_usb/vbussrc[/B] - external vbus OFF
Control App Development
Nook Tweaks :
Source
Nook-Color-usbhost-switcher ( verygreen's old app ) :
Source
- GPS
- Audio Input
- DVB-T
- Home-Screen Widget
