James Gardner

I have a Samsung SHG-E250 mobile phone on Orange pay as you go in the UK. I’ve also got a Belkin USB bluetooth dongle model F8T013xx1 and I wanted to be able to access the internet from my Debian laptop over GPRS. This article is a working solution but there is a lot about the intricacies of what’s going on that I don’t understand so whilst I hope this is useful, I make no guarantees!

Paying a Provider

The first challenge is the cost. Standard tariffs is £4 per MB which is frankly outrageous. There is a handy trick you can use if you want to use GPRS on Orange. If you have Pay As You Go in the UK you get unlimited GPRS data until midnight that day for just £1. It is called an “Orange Extra” and you and rather than internet access it is called “Orange World”. From your phone dial 450 free. Then choose options 3111 followed by:

1 - Unlimited data until midnight for £1
2 - 4Mb total valid for 30 days for £4
3 - A week’s unlimited access for £5

The amount is taken off your Pay As You Go Balance immediately and you are asked to hold until the service has gone through and you are sent a txt after a few seconds confirming you can start using the service. You can check your remaining balance, including the Orange World access you just bought by dialing 453. You can use the unlimited data for £1 extra each day if you like.

Setting up Bluetooth on the Desktop

Once the financial side is sorted out you need to set up your connection. If you have installed the standard Gnome desktop then the “bluez” Bluetooth stack will already be set up. Just plug the dongle in and you can start pairing the devices. Right click the Bluetooth icon on the gnome panel which appears when you plug in the Bluetooth dongle. Choose preferences, give your computer a sensible name and choose “Visible and connectable for other devices”. My computer is called dirac-0 which you’ll see in some of the output later on.

On your phone turn on Bluetooth and select scan for devices to pair with the computer. You’ll be asked to enter a 4 digit pin. Choose something memorable. A message box will pop up on the desktop. Click it, enter the PIN and the devices will be bonded. That’s the easy bit, now time to test the connection.

Playing with Bluetooth

Scan for devices:

james@dirac:~$ sudo hcitool scan
Scanning …
    00:1A:8A:86:6D:CE    SGH-E250

Find out about a device:

james@dirac:~$ sudo hciconfig -a
hci0: Type: USB
        BD Address: 00:0A:3A:7A:E6:53 ACL MTU: 1017:8 SCO MTU: 64:0
        UP RUNNING PSCAN
        RX bytes:10237 acl:210 sco:0 events:217 errors:0
        TX bytes:4609 acl:210 sco:0 commands:71 errors:0
        Features: 0xff 0xff 0×8d 0xfe 0×9b 0xf9 0×00 0×80
        Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
        Link policy: RSWITCH HOLD SNIFF PARK
        Link mode: SLAVE ACCEPT
        Name: ‘dirac-0′
        Class: 0×3e0100
        Service Classes: Networking, Rendering, Capturing, Object Transfer, Audio
        Device Class: Computer, Uncategorized
        HCI Ver: 2.0 (0×3) HCI Rev: 0×4102 LMP Ver: 2.0 (0×3) LMP Subver: 0×430e
    Manufacturer: Broadcom Corporation (15)

Ping a device:

james@dirac:~$ sudo l2ping 00:1A:8A:86:6D:CE
Ping: 00:1A:8A:86:6D:CE from 00:0A:3A:7A:E6:53 (data size 44) …
44 bytes from 00:1A:8A:86:6D:CE id 0 time 37.50ms
44 bytes from 00:1A:8A:86:6D:CE id 1 time 75.61ms
44 bytes from 00:1A:8A:86:6D:CE id 2 time 66.62ms
3 sent, 3 received, 0% loss

Connecting for Dial Up Networking

Once all that is working nicely it is time to search for a device with Dial Up Networking:

james@dirac:~$ sdptool search DUN
Inquiring …
Searching for DUN on 00:1A:8A:86:6D:CE …
Service Name: Dial-up Networking
Service RecHandle: 0×10002
Service Class ID List:
  ”Dialup Networking” (0×1103)
Protocol Descriptor List:
  ”L2CAP” (0×0100)
  ”RFCOMM” (0×0003)
    Channel: 3
Profile Descriptor List:
  ”Dialup Networking” (0×1103)
    Version: 0×0100

As you can see the device 00:1A:8A:86:6D:CE (which you know is an SGH-E250 phone from the sudo hcitool scan command you ran above) supports RFCOMM and on channel 3. It is important to make a note of the channel because you’ll need it for the next command:

james@dirac:~$ sudo rfcomm bind 0 00:1A:8A:86:6D:CE 3
james@dirac:~$ sudo rfcomm show 0
rfcomm0: 00:1A:8A:86:6D:CE channel 3 clean

This tells you that you now have your Bluetooth phone connected on /dev/rfcomm0. If you leave it too long after binding before trying the show command you might see this:

james@dirac:~$ sudo rfcomm show 0
rfcomm0: 03:00:00:00:00:00 channel 1 closed

In which case release and then bind again:

james@dirac:~$ sudo rfcomm release 0
james@dirac:~$ sudo rfcomm bind 0 00:1A:8A:86:6D:CE 3
james@dirac:~$ sudo rfcomm show 0
rfcomm0: 00:1A:8A:86:6D:CE channel 3 clean

Now you have a Bluetooth connection you are ready to set up your GPRS connection.

Testing Your Connection Settings

If you already know all the settings you need to use you can skip this bit and go straight to setting up the GPRS connection via PPP. Installing and playing with minicom isn’t strictly necessary, it will just help you track down problems more quickly.

First you’ll need a tool such as minicom.

james@dirac:~$ sudo apt-get install minicom

You need to add your user to the dialout group to use minicom as a non-root user.

Then create a configuration file:

sudo minicom -s

You get shown an options screen. In the “Serial port setup“ screen choose “A“ to make the

A - Serial Device : /dev/rfcomm0

Then choose “E“ to change the “Bps/Par/Bits“ to “57600 8N1“. You do this by pressing “H“ and “Q“. You can try 115200 later if 57600 works. Press ““ to go back to the main menu and choose “Save setup as..“ to save the settings as “bluetooth.dfl“ before exiting.

To use your new configuration type:

minicom bluetooth.dfl

If you have any problems it is worth running “sudo rfcomm show 0“ again to check you still have a clean connection. If not, release the connection and bind to the channel again first.

When you run this command for the first time the phone will ask you something like: “DUN connect with dirac-0″. Choose yes.

Once you are connected you’ll see a screen like the one below. Type the following to initialise GPRS:

at
ate1
at+cgdcont=1,”IP”,”orangeinternet”,”",0,0
atdt*99#

After each line you should see an OK message except after the last line when you should see a CONNECT as shown below.

If you were able to connect successfully, great. If not you might need to search on the internet for the correct settings for your provider and phone. In particular the atdt*99# line might need changing.

Setting up PPP

If you want your phone to bind automatically you can edit your /etc/bluetooth/rfcomm.conf so it looks like this:

#
# RFCOMM configuration file.
#
rfcomm0 {
    bind yes;
    device 00:1A:8A:86:6D:CE;
    channel 3;
    comment “Bluetooth PPP Connection”;
}

Obviously you’ll need to enter the correct channel and device for your phone based on the output you received earlier from running sdptool search DUN. You’ll then need to restart Bluetooth with:

/etc/init.d/bluetooth restart

I chose not to add the lines to rfcomm.conf because I want to always manually connect my phone to avoid the chance of running up any unwanted bills (of course just binding to the device doesn’t mean I am connected to the internet but I’m just being paranoid).

If you want to bind manually you should do so now:

james@dirac:~$ sudo rfcomm bind 0 00:1A:8A:86:6D:CE 3
james@dirac:~$ sudo rfcomm show 0
rfcomm0: 00:1A:8A:86:6D:CE channel 3 clean

Next create the file /etc/ppp/peers/bluetooth and add the following content. I had to play around with this for a long time so if it doesn’t work for you, take a look at other examples for your phone/provider and mix and match commands from different configurations until it does. This example is based on the one from here.

# File:
# gprs
#
# Description:
# Serial cable, IrDA, Bluetooth and USB pppd options for GPRS phones.

# Keep pppd attached to the terminal:
# Comment this to get daemon mode pppd
nodetach

# Debug info from pppd:
# Comment this off, if you don’t need more info
debug

# Show password in debug messages
show-password

# Connect script:
connect ‘/usr/sbin/chat -v -f /etc/chatscripts/bluetooth’

# Disconnect script:
# AT commands used to ‘hangup’ the GPRS connection.
disconnect /etc/ppp/peers/gprs-disconnect-chat

# Serial device to which the GPRS phone is connected:
# /dev/ttyS0 for serial port (COM1 in Windows),
# /dev/ircomm0 for IrDA,
# /dev/ttyUB0 for Bluetooth (Bluez with rfcomm running) and
# /dev/ttyUSB0 for USB
#/dev/ttyS0 # serial port one
#/dev/ttyS1 # serial port two
#/dev/ircomm0 # IrDA serial port one
/dev/rfcomm0 # Bluetooth serial port one
#/dev/ttyUSB0 # USB serial device, for example Orange SPV

# Serial port line speed
115200 # fast enough
#57600 # perhaps usefull with IrDA

# Hardware flow control:
# Use hardware flow control with cable, Bluetooth and USB but not with IrDA.
crtscts # serial cable, Bluetooth and USB
#nocrtscts # IrDA

# Ignore carrier detect signal from the modem:
local

# IP addresses:
# - accept peers idea of our local address and set address peer as 10.0.0.1
# (any address would do, since IPCP gives 0.0.0.0 to it)
# - if you use the 10. network at home or something and pppd rejects it,
# change the address to something else
:10.0.0.1

# pppd must not propose any IP address to the peer!
noipdefault

# Accept peers idea of our local address
ipcp-accept-local

# Add the ppp interface as default route to the IP routing table
defaultroute
# DNS servers from the phone:
# some phones support this, some don’t.
usepeerdns

# ppp compression:
# ppp compression may be used between the phone and the pppd, but the
# serial connection is usually not the bottleneck in GPRS, so the
# compression is useless (and with some phones need to disabled before
# the LCP negotiations succeed).

#novj
#nobsdcomp
#novjccomp
#nopcomp
#noaccomp

# The phone is not required to authenticate:
noauth

# Username and password:
# If username and password are required by the APN, put here the username
# and put the username-password combination to the secrets file:
# /etc/ppp/pap-secrets for PAP and /etc/ppp/chap-secrets for CHAP
# authentication. See pppd man pages for details.
# Example, Radiolinja operator pap-secrets:
# “rlnet” * “internet” *
#user “rlnet”
#user “Orange”

# Asyncmap:
# some phones may require this option.
#asyncmap 0xa0000

# No magic:
# some phones may require this option.
nomagic

# Require PAP authentication:
# some phones may require this option.
#require-pap

Now you’ll need to create the /etc/chatscripts/bluetooth referenced in the file above:

TIMEOUT 35
ECHO ON
ABORT ‘\nBUSY\r’
ABORT ‘\nERROR\r’
ABORT ‘\nNO ANSWER\r’
ABORT ‘\nNO CARRIER\r’
ABORT ‘\nNO DIALTONE\r’
ABORT ‘\nRINGING\r\n\r\nRINGING\r’
” \rAT
OK ‘AT+CGDCONT=1,”IP”,”orangeinternet”,”",0,0′
OK ‘ATD*99#’
CONNECT “”

and also the /etc/ppp/peers/gprs-disconnect-chat script:

#!/bin/sh
#
# File:
# gprs-disconnect-chat
#
# send break
exec /usr/sbin/chat -V -s -S \
ABORT “BUSY” \
ABORT “ERROR” \
ABORT “NO DIALTONE” \
SAY “\nSending break to the modem\n” \
“” “\K” \
“” “+++ATH” \
SAY “\nPDP context detached\n”

You’ll need to make this one executable otherwise it won’t be able to be executed when you disconnect (not that it seems to be a huge problem).

Finally, update /etc/resolve.conf to use the Orange nameservers:

nameserver 193.35.133.10
nameserver 193.35.134.10

That’s pretty much it. Now bring down any other interfaces you have connected such as wirless or LAN connections so that when you connect over GPRS your routing tables will be set up correctly:

sudo ifdown eth0

Now check you are bound, cross your fingers and connect:

james@dirac:~$ sudo rfcomm bind 0 00:1A:8A:86:6D:CE 3
james@dirac:~$ sudo rfcomm show 0
rfcomm0: 00:1A:8A:86:6D:CE channel 3 clean
james@dirac:~$ sudo pon bluetooth

The final line is what does the connecting. A message should pop up on your phone asking for permission to start DUN. Choose yes and a load of messages should fly by and you should find yourself connected!

james@dirac:~$ sudo pon bluetooth
AT
OK
AT+CGDCONT=1,”IP”,”orangeinternet”,”",0,0
OK
ATD*99#
CONNECT
Serial connection established.
using channel 3
Using interface ppp0
Connect: ppp0 <--> /dev/rfcomm0
sent [LCP ConfReq id=0×1 ]
rcvd [LCP ConfReq id=0×1 ]
sent [LCP ConfAck id=0×1 ]
rcvd [LCP ConfRej id=0×1 ]
sent [LCP ConfReq id=0×2 ]
rcvd [LCP ConfAck id=0×2 ]
sent [LCP EchoReq id=0×0 magic=0×0]
sent [PAP AuthReq id=0×1 user=”dirac” password=”"]
rcvd [LCP EchoRep id=0×0 magic=0×0]
rcvd [PAP AuthAck id=0×1 “Login OK”]
Remote message: Login OK
PAP authentication succeeded
sent [CCP ConfReq id=0×1 ]
sent [IPCP ConfReq id=0×1 < ms-dns3 0.0.0.0>]
rcvd [LCP ProtRej id=0×2 80 fd 01 01 00 0f 1a 04 78 00 18 04 78 00 15 03 2f]
Protocol-Reject for ‘Compression Control Protocol’ (0×80fd) received
rcvd [IPCP ConfRej id=0×1 ]
sent [IPCP ConfReq id=0×2 ]
sent [IPCP ConfReq id=0×2 ]
rcvd [IPCP ConfReq id=0×1 ]
sent [IPCP ConfNak id=0×1 ]
rcvd [IPCP ConfNak id=0×2 ]
sent [IPCP ConfReq id=0×3 ]
rcvd [IPCP ConfReq id=0×2 ]
sent [IPCP ConfNak id=0×2 ]
rcvd [IPCP ConfAck id=0×3 ]
rcvd [IPCP ConfReq id=0×3 ]
sent [IPCP ConfNak id=0×3 ]
rcvd [IPCP ConfReq id=0×4 ]
sent [IPCP ConfNak id=0×4 ]
rcvd [IPCP ConfReq id=0×5 ]
sent [IPCP ConfNak id=0×5 ]
rcvd [IPCP ConfReq id=0×6 ]
sent [IPCP ConfRej id=0×6 ]
rcvd [IPCP ConfReq id=0×7 ]
sent [IPCP ConfRej id=0×7 ]
rcvd [IPCP ConfReq id=0×8]
sent [IPCP ConfAck id=0×8]
Cannot determine ethernet address for proxy ARP
local IP address 10.34.152.3
remote IP address 10.0.0.1
primary DNS address 193.35.133.10
secondary DNS address 193.35.134.10
Script /etc/ppp/ip-up started (pid 7253)
Script /etc/ppp/ip-up finished (pid 7253), status = 0×0

Disconnect by pressing Ctrl+C or as a last resort, turning off Bluetooth on your phone.

Terminating on signal 2
Connect time 2.2 minutes.
Sent 29700 bytes, received 2104 bytes.
Script /etc/ppp/ip-down started (pid 7324)
sent [LCP TermReq id=0×3 “User request”]
Script /etc/ppp/ip-down finished (pid 7324), status = 0×0
rcvd [LCP TermAck id=0×3]
Connection terminated.
Garbled time

Sending break to the modem

PDP context detached
Serial link disconnected.
james@dirac:~$

You can then connect again if you want to with:

james@dirac:~$ sudo pon bluetooth.

If things don’t work out first time my advice is to either try to work out properly what all the options mean in the PPP configuration or just use a bit of trial and error from other examples which have been written for your mobile provider, phone model or operating system. By the way, I’m using GPRS to write and save this blog entry now so it does work!

Update If you don’t set the nameservers in /etc/resolve.conf they get set for you automatically and if you comment out the :10.0.0.1 line in the /etc/ppp/peers/bluetooth line it still all works.

After playing with VMWare yesterday and successfully booting Windows XP under Debian (after re-activating it because it complained of hardware changes) I quickly realised that I was going to rapidly run out of disk space if I continued creating new disk images. Since I want my files to be available on lots of different machines it was time to bite the bullet and buy an external hard drive. I looked on dabs.com and decided on the Western Digital 160GB Passport for £69.99. Before I ordered it I thought I’d head down to PC World (something I only ever do if I can’t wait for delivery) and had a look at their range in case there was something comparable. After deciding none of the products they had were good value I gave up and came home only to read on CNET that the FreeAgent Go (one of the drives I had looked at) was actually a very fast hard drive beaten only by the Maxtor OneTouch III Mini Edition in their tests. What is more, the 120GB version is a 7200rpm drive as opposed to the 5400rpm they tested so there was a chance the version in PC World might be even faster. In the end I drove back to PC World and bought it for £69.99.

The box is very nicely styled and when you open it you are greeted with a very simple instruction manual which says “This won’t take long”. It’s right. All you do is take the drive and the cable out of their packaging and plug them in. That’s it. You are then good to go. The USB cable it comes with has two plugs, one is for power and the other is for power and data. The cable is split so that you can easily plug the drive into USB sockets which are at opposite sides of your computer. If you don’t have two USB slots free, not to worry. The drive works perfectly well without having the one with “Power” written on it plugged in because power is still supplied by the other one marked “Power+Data”. If you read the instruction leaflet (which I didn’t) you’ll also notice that the drive has a whopping 5 years warranty. Seagate must be confident of the quality of the product.

One thing that really strikes you is just how small this drive is. Physically it is only fractionally larger than my wallet and my mouse is actually longer than the drive. When it is plugged in the base of the drive glows yellow and when you are transferring data the yellow light fades and comes back slowly in a very pleasing manner.

One other point worth mentioning is that the drive comes with some software. I don’t know what this does, and frankly I’m not interested so I just created a new directory on the drive and moved everything that was on there already to that directory in case I wanted it later. As a result of moving the hidden Autorun.inf the software doesn’t auto play when you plug the drive in and it no longer has the custom drive icon. Perfect.

At this point I decided to test the drive. Since CNET suggested a 10GB transfer should be possible in 10 minutes I tried transferring 270 MP3 and video files totaling 1.21GB. I was horrified to see it took 21 minutes and 5 seconds. Something was wrong

A quick look in device manager reveals that I have an Intel(R) 82801DB/DBM USB 2.0 Enhanced Host Controller -24CD on my IBM Thinkpad R50e. This page explains:

The 82801DB I/O Controller Hub (ICH4) contains three USB 1.1 (UHCI) controllers and one USB 2.0 (EHCI) controller, supporting up to six ports. Whether a port is controlled by one of the UHCI controllers or by the EHCI controller, and therefore whether or not it supports Hi-Speed, is up to some internal routing logic. I think the six physical ports (external to the ICH chip) can each be run either by the appropriate Universal Host Controller or the Enhanced Host Controller independently of all the others.

The EHCI driver is responsible for setting up the routing to the EHC or the UHC as appropriate. Either it’s not detecting the speed correctly initially, erroneously routing the hi-speed device to the UHC, or there’s a fault in the hardware or driver.

Sure enough, when I plugged the Power+Data cable into the other USB port the drive burst into life. Bottom line: if you do buy this drive for its speed you absolutely must make sure you have a Hi-Speed USB port to make proper use of it. Here are the real test results using the Hi-Speed USB port rather than the USB 1.1 port:

1.21GB music written to the drive in 71 seconds (about 17MB/second)
1.21GB music read from the drive in 78 seconds (about 15.5 MB/second)

The interesting thing here is that reading was slower than writing which strongly suggests that this drive is actually faster than my laptop’s internal hard disk which frankly is plenty fast enough for me! I also tried it with just the one USB cable rather than the two and I attached my USB hub, mouse, printer and keyboard to the other USB port to see if it made a difference. The results:

1.21GB music written to the drive in 73 seconds (about 16.5MB/second)

Basically it doesn’t make any difference. The two seconds could easily have been due to me not starting and stopping the clock accurately.

One final point worth mentioning is that the drive isn’t really 120GB in size. Most hard disk manufacturers like to say 1GB=1000Mb whereas in computing terms 1GB=1024MB. Consequently Windows describes the drive as 111GB capacity. This is still plenty big enough for my purposes though. The drive also comes pre-formatted as NTFS. If you are using Mac OS X or Linux you will need to reformat it to be something more appropriate or else install the FUSE NTFS driver to be able to use the drive. I’ll try that next.

Update (23/06/07): After investigating ntfs-3g I still think it is too new. Although the software itself is considered stable it requires more recent versions of software than are found in in Debian Etch stable. Although I could install it from testing I’ve learned the hard way that installing software from testing or unstable always causes problems in the long run.

The only filesystem which is natively supported under both Windows, Mac OS X and most Linux distributions is FAT32. It can handle partitions above 32GB as long as you don’t use Windows tools to format it (it would appear Microsoft would prefer you to use NTFS) but it works fine from Linux. The limitations main limitation is that FAT32 does not support files larger than 4GB but if you can live with that then it should be a fine choice.

To reformat your drive you’ll need to install dosfstools and if you prefer GUI interfaces to do this sort of things you can use gparted:

sudo apt-get install dosfstools gparted

To format the drive simply start gparted, select the correct drive and reformat it FAT32. To check it works disconnect and reconnect the device.

Once I’d formatted the drive I rebooted into Windows and re-ran the tests. The same transfer took 78 seconds. Slightly longer than with NTFS but not too bad. I did notice that transferring lots of small files is a bit slower and also that Windows’ time estimates are far too high when it starts copying which give you the impression to start with that FAT32 is a lot worse than NTFS.

Anyway, I’m very happy now. I have a drive which will work on virtually any modern computer with no drivers or filesystem tweaks and I can easily keep it with my laptop or even in my pocket and know I’ll always have access to my important files.

Update2 (25/06/2007): I’ve noticed the FreeAgent Go drive displays files sizes in property dialogs much faster than my laptop hard drive but that for small file sizes, such as my subversion code checkouts, the FAT32 filesystem is vastly less efficient than NTFS. 236MB small files take up 446MB space on NTFS and 1.1GB on FAT32.

Update3 (20/07/2007): On Debain Etch this drive frequently becomes read-only for no apparant reason. This is easily resolved as follows:

1. Get the sdparm package

sudo apt-get install sdparm

Find out your drive device (in my case /dev/sdb1)

sudo fdisk -l

Clear standby mode:

sdparm --clear STANDBY -6 /dev/sdb1

I must admit I don’t fully understand what this does but it looks like it is clearing a flag on the drive itself which causes it to go read only. Anyway, it does the trick for me!