Tuesday, 31 August 2010

Saturday, 21 August 2010

Meta-Choice


We should consider the meta-choice.

Online image editting

Recently, I had to do some image editing for my friend's blog. I did not have Gimp installed on my Arch system and Gwenview can do some cropping but not much else. Some time ago, I was thinking of having a site that allows editing of images online. It was just a random thought and I did not have the knowledge to implement such a site. However, now that there was a need for such a site [because I did not want to install image editing tools as do it very rarely], I googled for it and found this nice site to help me out. It had a Photoshop-like UI and worked nicely for my needs. I was glad to get my work done [and to know that my idea was feasible].

John Cleese on creativity and subconscious

Sunday, 15 August 2010

Connecting to BSNL GPRS on Arch linux

Popular Indian ISP BSNL is notorious for bad customer care. This makes the use of less popular technologies quite an experiment. Cutting out the elaboration of my experiments, let us look at the procedure for connecting to the internet using BSNL GRS. I used wvdial for the purpose and find it quite flexible. Internet access requires the cell phone to be connected in "PC Suite" mode. I shall describe the procedure for two phones:
1. Nokia XpressMusic 5130
2. Samsung Corby

Lets start with Nokia XpressMusic. To connect it from Windows, use Nokia's PcSuite; and add the following configurations manually:
1. access point name: bsnlnet
2. dialing number: *99#


Now let us look into connecting Nokia XpressMusic using linux. Firstly, get wvdial and its dependencies installed on your system. Connect the phone and check dmesg output to get the name of the modem device. Run wvdialconf to set the baud in /etc/wvdial.conf. Then edit /etc/wvdial.conf as follows:

Init1 = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Init3 = AT+CGDCONT=1,"IP","bsnlnet"
Password = <your phone number>
Check Def Route = 1
Phone = *99***1#
New PPPD = 1
Modem Type = USB Modem
Stupid Mode = 1
# let wvdialconf set this for you
Baud = 460800
Auto DNS = 1
# This command is essential.
Dial Command = ATD
#  put your modem name here
Modem = /dev/ttyACM0
ISDN = 0
Username = <your phone number>


The same configuration shall work for the Samsung Corby. Finally, to connect Samsung Corby using the PcSuite, use the following configuration.
1. access point: bsnlnet
2. dialing number: *99***1#

Connecting to wireless LAN on Arch linux

Recently, I successfully accessed wireless LAN on my Arch linux. This post shall be a documentation of the same.
Following is the part of lspci -k output of interest here.

02:00.0 Network controller: Broadcom Corporation BCM4311 802.11b/g WLAN (rev 02)
        Subsystem: Hewlett-Packard Company BCM4311 802.11b/g Wireless LAN Controller
        Kernel driver in use: b43-pci-bridge
        Kernel modules: ssb


To get the driver, I followed the steps in the wiki. I edited the MODULES line of my rc.conf as follows:

MODULES=(acpi-cpufreq cpufreq_ondemand cpufreq_conservative cpufreq_powersave cpufreq_performance !pcspkr !snd_pcsp !b43legacy b43)

Using wireless LAN was fairly simple with the following sequence of commands:

# wake up the interface
ifconfig wlan0 up
# scan for wireless networks in range
iwlist scan
# join the desired network based on their essid
iwconfig wlan0 essid "<name>" key <password>
# for automatic detection
iwconfig wlan0 channel auto
# obtain the lease of an IP
dhcpcd wlan0

It is also easy to end a wireless session.

# release the interface
dhcpcd -k wlan0
# exit dhcp
dhcpcd -x
# turn off the interface
ifconfig wlan0 down