Do be careful with the microsd cards.. sebab beli yang salah, most probably it wont boot... i bought one kingston 16gbC4, it didnt boot. but another sandisk 2gb boots perfectly..

depends on the compatibility...

for some other cards :
the 2012-09-18-wheezy-raspbian version didnt work out well..
tried fedora remix worked.. arch worked too..

well, this is what i tried,

used thin eraser to rub on the pins of the microsd n sd adapter...
den used a ciplak reader and did the copying job..

it works out well after all..

If anyone faces frequent reboot, get a better power supply.
If hdmi flickers too much, try to boost hdmi using config.txt

just to inform if in case its not discussed here..

Seriously ? i am from sitiawan.. SMK Methodist ACS Sitiawan..

so far.. element14 n rs..

ssh is something like cmd, but far more powerful...
can direct file transfer via sftp on same protocol..

if u gonna do programming (electronic stuff) via raspberry pi..
get notepad++, connect via sftp..

So that u can edit codes easily n use the board only to compile..

Either RS or Element14
Check out if other LYN members are selling it out..

Good luck..

This is wat m doing with my pi currently..
To read signal from industrial sensors..

Not pretty though.

its a small prototype to detect obstacle in 4 different direction using 4 photoelectric sensor and a reset point using inductive proximity sensor with 30V power supply. and transfer data wirelessly..

made the console program with c++ n wiringPi library..

the setup :



This post has been edited by satz: Nov 20 2012, 08:14 PM


Attached thumbnail(s)

with wireless (cheap adapter).., internal database storage with a web output running apache or thttpd, arduino is no where nearby..

This is casing i did..
Able to reduce temperature from 50 to 35..

Currently the casing is in my office... only board with me.. give me couple of days.. gonna test it in higher ambient temperature area.. with another 4" fan..

Will get a graph plotted.. But do note that the fan is powered via an external power supply.. a 24V DC 4.5A PSU... as its needed to power up 5 photoelectric sensors...

self made casing v2 ! hehehe...
pi board -> self made level shifter -> 24V power supply -> 5 sensors

sensors are powered by 24V psu.. and by using phototransistor optocoupler, hooked up to
pi gnd, 3.3v n GPIO pin.. pure pi.. nor arduino involved.

yeah.. a small rnd.. without using plc.. planning to use d pi to read 15 sensors simultaneously.. using multithreading in c++... so far done with 5.. with writing data to sqlite3 n produce output with nginx n php5..

What kind of home automation device ur using..? Or self built..? If self built u gotta play with the gpio pins..

Hello everyone. Finally i have already completed my project.
A wireless counter with web access and database storage.

- 4 threads for counting
- Graph for the counting time
- nginx web access (PHP links to the local sqlite3 database)
- database using sqlite3
- sensor voltages are passed to the pi via a level shifter like board
(Self made)
- ambient temperature almost 40 degrees, 2x 12cm 24V fan is used.

Sensor used :


The board to get readings :


The whole device : (pi inside, 4A psu, sensor board)


Terminal program to read data and safe to database :


Web output :


To view saved data :

well, we have huge number of fixed object moving on 4 different track but in 1 single line,
so the objective was to count the number of object moving across the sensors
as well to detect how many are broken in 1 complete round.

You can classify it as a normal electronic counter.
So, instead of pulling up long wires or long hdmi cable..
an internal web server and database server(sqlite3) will be running.
The raspberry pi will be connecting to a nearby router via a wireless adapter (edimax).

Any devices with access to the router and with web browser can view the web output.
Its an cheap wireless counter.

This post has been edited by satz: Jan 3 2013, 03:15 PM

Sensor model : Photoelectric sensor 10-30V NPN

The code in C++ must have multiple threads so that it could detect simultaneously for high speed movements.

Yeah, totally wireless, But do note that wireless adapter could disconnect every now and then, for a total headless operation,

Create a script to detect whether wireless is connected and run that script in a screen multiplexing software like, "GNU Screen" or use crontab, scheduling software.

Yup, port forwarding will allow external access.

For the wireless adapter part, m not that sure on whats the issue, but i guess my issue was the distance
or the adapter power down when no activity. Because when the browser access the web server,
the wireless adapter tend to work non stop.. But when no devices access the internal webserver,
the wireless adapter tend to disconnect from the router. So i had to restart the whole pi.
The distance between the router and rpi box is approximately 6 meters.

So create a script which will check the wireless connection every 1 or 5 minutes and
script run ifconfig wlan0 down and ifconfig wlan0 up if in case connection breaks.
As the whole operation is headless, GNU screen is very useful. The program/script will
still run eventhough our terminal session ends.


Level shifter with circuit diagram planning - 3 days
C/C++ program - 7 days
PHP web output - 4 days

Took me approximately 2 weeks.