Mobile web devices are different from ultra compact PCs, primarily by the fact that MWDs are meant for a minimal set of functions, such as web browsing and playing media. They may not be meant for tasks such as word processing or other office/business purposes. Also they may not contain a full OS such as Windows Vista (although this is possible), but may be instead be based on a thin mobile OS such as a trimmed down Linux distribution. MWDs would also try to be low on power consumption and may possibly target for 4 hours or more of continuous operation between re-charges.

Most MWDs available now are trying to provide many features including media player, photo browsing and basic editing, instant messaging among others. They also provide a reasonable to large amout of storage space, aimed at media storage. However, I believe that in addition to such all-in-one devices there is a huge market for a pure browser device which is wifi enabled. Such a device would directly launch the browser on startup and provide most of the browser features (such as flash, media codecs) to enable browsing any website, and for playing streaming audio/video. At a price point of less than $100, such a device would be attractive to many.

You may read further about this new revolution of devices at the following links:

1. Intel’s site on Mobile Internet Devices (MIDs) & Ultra Mobile PCs (UMPCs)

2. Linux-based tablets and webpads at LinuxDevices

3. Nokia 770 internet tablet

4. Pepper pad

5. Apple iPhone and iPod touch

I know good C/C++, and little bit of python. Although I am not an expert at python, I thought using a scripting language would be much easier here, and I was not wrong. Here’s the code:

import string

#Look for what we want
f_input = open(”log1.txt”)
f_output = open(”result.txt”, “w”)

slist = f_input.readlines();
i = 0
prev = 0
prev_orig = “00″
while i < (len(slist) - 1) :
if slist[i].find("Message_Marker") != -1:
s1 = slist[i+1]
s2 = s1[22:24]
d1 = string.atoi(s2,16)
d2 = (d1 >> 1) & 0×1f # version is bits 1-6
if d2 != (prev+1):
if ((d2 == 0) and (prev == 0×1f)): #This is normal rollover
d2 = 0 #dummy
else:
f_output.write(prev_orig + ” ” + s2 + ” ” + hex(prev) + ” ” + hex(d2) + “\n”)
prev = d2
prev_orig = s2
i = i + 1

f_output.close()
f_input.close()

I am absolutely certain that the above code can be written in much better ways, but the above works well for the purpose. But the point is, it took barely about 15 minutes to develop the above script, and I was happily parsing logs and finding the lost sections.

I look forward to trying out some ruby scripting. Of course, I do not want to compare python/ruby here (that is being done in lot of other forums), I rather choose to play with both and take my time to settle into one of those, or use both in places appropriate.

VBI stands for Vertical Blanking Interval. In analog video display, such as a CRT, a video frame is shown by drawing horizontal lines from the top to the bottom of the screen. Once a frame is completely drawn, the beam has to travel back to the top left, to start drawing the next frame. Since there is nothing to show while the beam retraces, this interval is blanked and hence called the vertical blanking interval.

VBI Data

During vertical blanking time, no video is shown. So the display is not consuming anything from the incoming video signal. This interval effectively leaves open a chunk of bandwidth that can be used for data communication. To keep things simple, the horizontal lines (referred to as just ‘lines’, henceforth) are continued to be transmitted during the vertical blanking interval, but the lines do not contain video. Each VBI line, or group of lines may contain data, encoded as per a variety of standards. The most common used VBI service is the closed caption service, which is used to show text subtitles.

To ensure that VBI data goes wherever the video goes, VBI data is actually encoded as video. This allows VBI data to be transmitted transparently across any carrier media (Over The Air (OTA), cable, satellite, fibre optic cable etc) that is designed to transmit the video signal.

Raw and Sliced data

The hardware that receives VBI data may just sample the VBI lines to collect the data bits, with no knowledge of the type of data it contains. This is called raw data. The raw data may then be processed by software to interpret the contents.

The other possibility is to have the VBI hardware interpret the VBI data, based on the type or standard used on the line(s). The output in this case is extracted information such as closed caption characters, or data packets. This is called sliced data.

Typical VBI data extraction hardware supports both modes. The ’sliced’ mode is much more useful, since a lot of low level functions such as data extraction , error correction are handled by the hardware. Raw data is primarily used to work with non standard VBI data, and for re-encoding unmodified into an output video signal.

A note on Interlaced video

NTSC analog video uses interlaced video. This means that even though the video has 30 pictures (frames) per second, the video is transmitted as 60 fields by splitting each frame into an odd and even field.

How much data can VBI carry?

In NTSC, the VBI consists of 21 lines. Lines 1 to 9 are ‘reserved’ for television timing signaling. Lines 10 to 21 are available for data transmission. Line 21 is widely used for closed captioning, hence the available lines are 10 – 20, a total of 11 lines.

Each VBI line can transmit up to 288 bits. At a rate of 60 fields per second this amounts to a raw line data rate of 17, 280 bits per second. Note that actual useful data rate would be much lower, due to packetization and error correction overheads.

Externally, the voq resembles a stick phone, rather than a PDA. Though a bit on the bulky side, the voq is very solid to hold, and the grooves in the middle of the sides give added support while holding in the hand. Though bigger than a typical mobile phone, the voq can easily slip into a jeans pocket.

The keypad is a very intelligent design, which has normal numerical keypad on the outside, but once flipped open, acts as a full alpha-numeric keypad (called a thumbpad). It is pretty easy to operate as well.

Voice quality and reception are excellent. I am seeing better reception than any other mobile phone I have owned.

The Windows mobile software is easy to use – especially if you are already a Windows desktop software user. It supports the usual set of PDA applications plus media players, Java support etc. If you have data support with your carrier, you can browse internet and send/receive emails. You can also use Outlook as your email client.

I could not get a car charger for this phone. However, I was able to use a motorola car charger of another phone; and it works well.

It has an SD slot and you can use it to store any kind of file that the windows software can open. You can even play a .wmv movie from the SD card, or play mp3 files. You can also read pdf, view presentation slides, read Word doc etc ..

Connection to PC is over USB or IR. There is no bluetooth. The USB connector is proprietary, so you have to use the included cable. I wish they provided a mini USB instead.

· The function should not hold or refer to any static data. Static data is non-stack data that is statically located for the lifetime of the program. Any function that refers to static data would refer to the same copy, and can potentially step on each other if the function is concurrently executed.

· The function should not call any other non-reentrant functions. This seems like an obvious requirement, but it needs special attention since reentrancy of a library function can easily get overlooked. For e.g., the library function ctime returns a character pointer, and invocation of ctime can make a function non-reentrant.

· The function should not return a pointer to static data.

The Backus-Naur Form (BNF or Backus-Naur Form) is a formal mathematical way to describe the grammar of a programming language.

BNF is used to formally define the grammar of a language unambiguously. The definitions of a programming language in BNF can be made to be so precise that a parser for the language may be created automatically from the BNF using compiler-compilers such as YACC (Yet Another Compiler Compiler), PRECC, COSY etc.

BNF specifies the language grammar as a set of rules. Each rule is called a ‘production’, and have the general form:

Non-Terminal ::= Alternative1 | Alternative2 …

A non-terminal symbol is a symbol that may be expanded further into terminal and/or non-terminal symbols. A terminal symbol cannot be further expanded, and ends the production. Each alternative on the RHS may be a terminal or non-terminal and are separated by ‘|’. All strings are treated as case sensitive.

Some examples:

a) while_statement ::= while logic_expression do statement

b) The ‘for’ loop in C++ may be represented as:

for ( InitExpression ; CondExpression ; LoopExpression ) Statement

The InitExpression is executed once in the beginning and then the CondExpression is executed. If CondExpression evaluates to true, then the Statement is executed. At the end of the iteration (execution of Statement), the LoopExpression is executed and CondExpression is evaluated and the iteration repeats until the value of the CondExpression is false.

All the three expressions (InitExpression, CondExpression, LoopExpression) are optional. For eg. the following is a valid for loop that executes Statement infinitely:

for(;;) { Statement }

With above information on for loop, the BNF production may be written as follows:

ForStatement ::= for ( [ InitExpression ] ; [ CondExpression ] ; [ LoopExpression ] ) Statement
InitExpression ::= expression | declaration
LoopExpression ::= expression
CondExpression ::= expression

1. TechOnline webcasts

2. WindRiver Web seminars.

3. Microchip web seminars

4. Radisys Webinars

4. QNX web seminars

I used this in my recent trip to SFO. I was expecting it to lose satellite signal while driving through narrow roads between tall buildings (my earlier GPS – Garmin eMap did not hold a signal in same conditions), but it held up extremely well. The turn by turn directions are pretty good.

The internal memory is a bit less (24 MB) for detailed map, but sufficient for most situations. I think I can load up to 1/3 of California into this. You can always load up new maps easily through the USB interface. The screen is somewhat small, but the navigation text is pretty big, and most of the time that is all I need while driving.

For the price, it is an excellent value for money. I haven’t seen another GPS that is color screen, both hiking and vehicle navigation use, turn by turn directions (no voice, though), excellent satellite signal reception and loads of other features. There are some cool games too.

My favorite is the ‘highway’ page, which shows a 3-D view of the road ahead, and the next turn shows up as a sign post. The 3-D view is not same as the 3-D feature some of the GPS’s offer. It is much simpler in eTrex, but very useful.

The short clip below shows how the GPS shows an upcoming turn. As shown in the clip, the GPS can be configured to ‘zoom in’ on the turn. Note that the vertical color stripes on the screen are due to the artifacts in the video clip, and NOT of the GPS itself.

1. Configuring Wordpress and the web server for allowing uploads.
2. Uploading the image to a website directory.
3. Linking to the image from your post.

1. Configuring upload

If you are not the administrator, please contact the administrator to check whether upload is available. Most likely, this step has been already performed and you should be able to upload using steps 2 and 3. If step 2 fails, contact your administrator.

– Configuring wordpress if you are administrator : to be added–

2. Uploading the image

a. Log into Wordpress with your username and password.

b. On the admin tab, click on ‘Upload’. You should now see the upload page. Click on ‘Browse’ and browse to the file in your PC that you want to upload.

c. Give a description of the picture in ‘Description:’

d. Leave ‘create thumbnail’ at the default ‘No Thanks’, unless you have specific reason to modify it.

e. Click on ‘Upload file’

f. You should see something like below:

————————————————–
File uploaded!

Your file sample.jpg was uploaded successfully!

Here’s the code to display it:

The HTML code appears here.

Image Details:
Name:sample.jpg
Size:45.69 KB
Type:application/x-zip-compressed
————————————————–

g. Select the html code fragment completely and copy it.

Adding the image link into the post

a. Open the post where you want the image.

b. Go to the exact place inside the post where the image shoould appear, and paste the html code that you copied above.

c. Save the post and view the post to see whether the image appears correctly.

Tips

1. If you are uploading a picture, be aware of the size (such as 320 x 240 pixels) of the image that would best fit into the post. You may want to re-size your image to this target size before uploading. To resize, you can use any photo editor application. If you are using a digital camera, then it surely came with a photo editor application. Or you can use free ones such as Gimp.