Monday, August 6 2012

How to use an android phone as a GPS receiver with GPS-less tablet using only GPL software....

... or how to use GPS-less tablet as big screen GPS car navigation. The setup that I tested:

- tablet Sanei N10 Deluxe with Android 4.0.3

- Samsung Galaxy S2 with CyanogenMod9

The tablet has no GPS receiver, so my favourite navigation/tracking OSMAnd cannot be used directly. To solve that problem I downloaded BlueGPS for the tablet and BlueNMEA for the phone. BlueNMEA works as GPS data server, the location is transmitter over bluetooth to BlueGPS on the tablet. BlueGPS uses "mock location" function to provire real GPS location for all the software runnng on the tablet.

How to set it up?

1. Allow use "mock locations" in

Settings -> Developer Options -> Allow mock locations on the tablet.

2. Pair tablet and phone using normal bluetooth functions in

Settings -> Bluetooth

3. Start BlueGPS on tablet

4. Start BlueNMEA on the phone

BlueNMEA before connection 5. Wait for the tablet to appear on devices list

BlueNMEA connected

6. As soon as the phone GPS get fix the info is passed to the tablet, so it can be used by i.e. OSMAnd or any other navigation software.

Thursday, August 2 2012

OLED icons on Wacom Intuos4 Wireless PTK-540WL - part 2

Full workflow how to get a custom icon on Wacom Intuos4 WL (this doesn't work for other Intuos4 family members!)

Make a 1-bit 64x32 pixels image. Let's say it's the recycling symbol:

recycle icon 64x32 1-bit png

Save it to PBM format, raw version. GIMP is perfect for that. Open the newly created file in a text editor. The header should look similar to this:

P4
# CREATOR: GIMP PNM Filter Version 1.1
64 32

It means that we created "portable bitmap/binary" using GIMP and the dimensions are 64 by 32 pixels. The rest of the file contains actual image, saved in 256 bytes, 8 pixels per byte. Some PBM icons here or here (full pack).

Now strip the header and save the "raw" icon. The file should hve exactly 256 bytes. If it has more or less it might mean that your text editor cannot handle binary files (try vim!) And again you can download "raw" icons - link above (same as PBM icons). Save the file to "recycle.i4wl" or download ready "recycle" icon from the pack.

Now connect the tablet using bluetooth connection. If you have applied the patches from this entry (I'll update the info here if the patches are accepted to the mainline kernel) you should see some oled_*img files in /sys/class/hidraw/hidraw(dev_number)/device directory. Each of those 8 files represents one icon on wacom Intuos4 wireless tablet. See this entry for information how to set the icon on your tablet using "dd" command. Hopefully setting the icons will be included into wacom gnome-control-center panel (any volunteers? ;-) )

Come back later to see how to batch create icons!