GPS evolution

My first Bluetooth GPS was the BT-308.
Good device. But the old one. And it has a very long start time - sometimes 5-6 minutes. I used it for 4 years. During this time, new chipsets was invented: sirf-III and later MTK. MTK is very popular nowadays.
A year ago I bought on ebay iblue 737 (MTK chipset).
And fell on its often problem - static navigation (or rather its problems). There are as follows: you start to go, but the chip sees it a few seconds later. Therefore, it reports position with little delay. Increasing update frequency to 5 Hz did not solve the problem. But this is compensates by its sensitivity. He catches satellites everywhere. Inside the car, under the car seat, in the house... Recently, I had to go with the old BT-308 - satellites lost between high buildings. With iblue 737, I already forgot about this. Very quick start. Economical - bluetooth switched off automatically if there is no connection. It allows longer working time from one charge. USB part is not soldered inside and used only for charging.

I read on gpspassion forums that new MTK firmware solved static navigation problem and semsons.com sells GPS with the new firmware. I stuck with iblue 747. It can work as a logger as well. Ordered device was received very quickly and then was tested. Static navigation problems seems to be fixed. No delays. Iblue 747 can be connected via bluetooth or USB . Economical. As a logger, it worked for 3 days on one charge and is not discharged. I did not try longer. Here's a log in Google earth

qq2440 and bluetooth GPS

I have created an application. This application based on printUI example from Windows CE. It creates COM5. This port you should select in iGo for GPS.

Application is here. I have copied it to SD card.

I assume that you have enabled bluetooth in windows CE as I described in previous post.

Start application in your windows CE device. It displays small icon in system tray.

If you start application first time, do the following:

Click on icon. The main window is opened.
Turn on your bluetooth GPS.
Press "inquiry" and wait. After 1 minute you should see your GPS in list.
Select your GPS and press OK. Window closes and you can use your GPS now.

You don't need to repeat inquiry. You do this only once - first time. Program writes in registry correct values for next runs.

For second and next runs after reset - only start program. Icon in system tray says that port is open. You can run iGo now.

If you want to delete all registry keys written by this program - press "Deregister" and make inquiry again.

qq2440 + iGo8 + bluetooth howto

How the stuff works

Part 1: iGo

First of all you need iGo 8 on SD card. In iGo8 install directory (StorageCard/NavNgo/iGO8) find file SYS.TXT and open it. Change/add the following:

[interface]
resolution_dir="800_480"
vga=0

[rawdisplay]
highres=0
screen_x=800
screen_y=480

If something missing – add it, if something present – change it. 800x480 – my screen resolution. If you have different resolution – change this numbers to yours. Now you should be able to start iGo.

Part2: BT Dongle

Open WinCE platform builder.
Open your project.
Open “Communication services and networking – Networking PAN – Bluetooth – Bluetooth protocol stack with transport driver support”.
Delete all except “Bluetooth stack with integrated USB driver”.
Now clean and build your platform.
After building and loading new platform you should be able to start Bluetooth dongle.
Go to “Settings – Control panel”. Double click on “Bluetooth device”. In opened window press “Scan Device”. You should view Bluetooth devices in range.

Part3: You need to open virtual COM port and associate it with Bluetooth. I’ll describe it later

GPS and qq2440 (continue)

GPS works. I have connected bluetooth USB dongle and bluetooth GPS. And there is a sample in Windows CE platform builder for virtual com port. I made some changes in it. Here is the results.

Navngo IGo 8 on qq2440

IGo 8 is running on qq2440. Finally something good. Now I'm looking for RS232 GPS.

Buildroot for qq2440 (continue)

I compiled buildroot with external toolchain, because of internal buildroot bug. It seems to be exist in last release. When I tried to compile buildroot and toolchain for arm - it didn't work. My board didnt recognize this filesystem.
Yesterday I downloaded buildroot snapshot "buildroot-20090420". Internal toolchain is OK now. And almost everything is compiled now. You only need to choose target architecture "arm" and cpu "arm920t".

Update 20.Aug.2009
Use updated manual

Building root filesystem for qq2440 with buildroot

Download buildroot from http://buildroot.uclibc.org/downloads/
I'm using 2009.02 release.

Download eldk for compiling
here
This is an iso image. Burn it and install it. I installed 2 versions (with software FP and with hardware FP) in /usr/local/cross. Actually we need to compile with software FP.

#tar -xvjf buildroot-2009.02.tar.bz2
#cd buildroot-2009.02
#make menuconfig

Now select:
Target architecture - arm
Target architecture variant - arm920t
Target ABI - EABI

Toolchain:
Toolchain type : External binary toolchain
Core C library : libc-2.6.so
Libraries to copy : clear all
Enable large file support - check
Enable RPC - check
Use software floating point by default - check
Build c++ compiler - check
External toolchain path : /usr/local/cross/usr

Target filesystem options:
Uncheck all
tar the root filesystem - check
Compression method : bzip2

Exit, save

#make

Root filesystem exists in binaries/uclibc

Now copy all libraries from /usr/local/cross/arm/lib to rootfs/lib. I need to explore what libraries we need exactly.

Deploy image to the board. I'm booting from nfs and in this configuration you can see linux booting in console.

Thanks for help to Leshak

Update 07-Mar-2009:
Tool chain: Libraries to copy:
ld-linux.so.3 libcrypt.so libdl.so libgcc_s.so libm.so libnsl.so libpthread.so libresolv.so librt.so libutil.so libc.so.6

Update 20.Aug.2009
Use updated manual