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 Raspberry Pi, Rm100 computer that beats iPhone4S

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satz
post Jan 5 2013, 09:09 PM

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QUOTE(aba9785 @ Jan 5 2013, 09:05 PM)
my friend last time try to check for wifi data collision thing using an app on his android phone
he use this method to find/locate best location/placing for his config/setup.
let me ask him what is the name of the app.

not sure if anyone else know of the app name/other method to check for wifi data collision thing
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u mean due to the wifi channels ?

satz
post Jan 5 2013, 09:23 PM

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if i am not mistaken usually due to channel overlapping,

channel 1,6,11 are the best as most router comes with either channel 6 or auto channel. But the weird part is my router is the only one in the office.

Or could it be the adapter self sleep when there is no activity ?
satz
post Jan 5 2013, 11:58 PM

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QUOTE(aba9785 @ Jan 5 2013, 09:27 PM)
hmm... u seems to know more than me  blush.gif

r u doing it as final year project?
not sure if ur lecturer will allow u to put that problem (wifi issue) as future enhancement or not.
or just pretend everything is ok for the first 30 mins  laugh.gif
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No la, i just came across the channel overlapping part when we r trying to bond
& link aggregate multiple network interfaces in linux. When wireless networks
under same channel, link aggregation works but bandwidth doesn't multiply.

Then only i found out about it in wikipedia : (channel 1,6,11)
http://en.wikipedia.org/wiki/List_of_WLAN_channels

Not final year, its a small R&D for a factory (counting purpose), wireless & portable.

Wifi do disconnect, but there will be a script running every 1 minute, so
wifi will reconnect automatically. smile.gif

I cant submit this as my fyp either because m pursuing chemical engineering. tongue.gif
satz
post Jan 6 2013, 12:38 AM

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QUOTE(I<3LYN @ Jan 6 2013, 12:31 AM)
I just made a laser-cut clear acrylic case for my pi  brows.gif

if anyone want a laser-cut acrylic case, please let me know  biggrin.gif
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Looks fabulous..! How much does this cost.??
satz
post Jan 6 2013, 07:33 PM

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QUOTE(aba9785 @ Jan 6 2013, 03:41 PM)
i see. so u r using a script to reconnect every minute, seems like a workaround but in case, i think should be ok
cos cheaper n less work  thumbup.gif
UGPM
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Precisely, cheaper alternative.. smile.gif
satz
post Jan 6 2013, 10:10 PM

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QUOTE(azrash @ Jan 6 2013, 09:37 PM)
this is a bit off topic from raspberry pi, but it is regarding Rpi's alternative, the ODROID. it is getting an official nightly from CyanogenMod. not surprising since it is an Exynos based device, but hell. tongue.gif

can refer at the cm dev's G+ posts here https://plus.google.com/115049428938715274412/posts
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Sounds interesting, price is kinda high compared to Rpi.
But the specs are impressive !
satz
post Jan 10 2013, 02:41 PM

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QUOTE(quikstep @ Jan 10 2013, 12:44 PM)
I have this issue from my 2nd Pi. Only this Pi behaves like this.

Sometimes when I pull anything out from the USB slot (wireless adapter, keyboard/mouse), this Pi automagically reboots. Meaning, it actually lost power and then powered up.

I'm 100% sure there are enough power into the Pi bcos I'm using the adapter for iPad 5V/2100mAH. VERY annoying when I'm coding.

Anyone else?
*
Well, i used to have this issue previously but it happens when i plug in something.
Yeah very annoying when coding. But after few googling.. found out its because of
the resettable fuse (polyfuse).

So, its recommended to use a usb hub connected to the usb port on the pi instead of
directly connecting it (for hot pluggable devices)

QUOTE
Don't hot plug USB devices directly into the PI, if you must hot plug plug into a hub instead!

Its called "the rush in current problem", and it makes that the current PI itself is non "hot pluggable", note that the revision 1 PI was hot pluggable, as the two polyfuses prevented any rush in current because the fuses had a non zero resistance. But in the current board there is literally zero resistance between the PI's 5V supply, and any USB device you plug in, that means that if you plug in any USB device with empty power decouplers, (which act as a complete short for a very small time) then you are actually simply shorting the 5V when you plug de USB device in.

The polyfuses in the revision 1 board however caused much greater problems than this problem, and for that reason have been removed.
Its possible and likely the hot-plug problem will be solved in a (final?) redesign of the PI by placing tiny resistors (smaller than 1 Ohm) back in the power path to the USB device.
However, if you have an USB hub plugged into the PI, its normally protected against the rush-in current so you can safely plug in an USB device into the hub.
As the current PI only has two ports normally there is no need/possibility to hot plug anything in anyway, (without a hub) as the two ports are reserved for a mouse and a keyboard, unless you want to hot plug the keyboard. If you want to plug anything in beyond that you would already use a hub, and as said, you can hot plug safely into a hub.

satz
post Jan 10 2013, 03:43 PM

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QUOTE(aba9785 @ Jan 10 2013, 03:42 PM)
are there any confirmed working powered hub that is confirm working for rpi (prefer less fault, less reset)

even though i m using a powered hub, my house there sometime got minor power surge/spike, changes in power voltage.

so far i dont plan to get voltage regulator...  not sure if anyone  facing this issue?
*
i am not sure about the others, but vztech 7 port one worked just nice for me.
satz
post Jan 10 2013, 03:55 PM

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QUOTE(Fubar20 @ Jan 10 2013, 03:50 PM)
biggrin.gif I am using this powered hub also.
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cheap and good..
satz
post Jan 13 2013, 09:24 PM

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QUOTE(totally_skint @ Jan 13 2013, 09:11 PM)
Is this a powered hub?

Do they sell this model without the adapter?
I got enough adapters in my junk box. tongue.gif
Would there be any internal difference between the two products (if available that is)

I have seen other brand powered hubs (you can see the power socket) sold without the adapter but wondered if they also removed board components too.
Actually I'm not even sure the power socket is inside the hole. rolleyes.gif
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Yeah, its a powered hub, i dont remmember the power rating, plug sudah hilang.. smile.gif
satz
post Jan 22 2013, 12:49 AM

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QUOTE(totally_skint @ Jan 21 2013, 11:58 PM)
Bought mine at Sri Computer Low Yat.
RM23
Comes with 5V 1.0A adapter.

I'm thinking of cutting off the 5V line to prevent backfeed.
Will that stop the hub completely like when you turn off the side switch?
*
it will stop powering the hub.. smile.gif
satz
post Jan 22 2013, 01:22 AM

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QUOTE(totally_skint @ Jan 22 2013, 12:58 AM)
How about putting a diode across the cut line to prevent backfeed and yet to use the hub with or without the power adapter?
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I doubt it would cause any issue.. as long the diode supports the power rating..
satz
post Jan 24 2013, 03:59 PM

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QUOTE(Aeon89 @ Jan 24 2013, 02:07 PM)
haha , look too naked tongue.gif unless built one with lego which i saw rather interesting. time to order and learn how use a Raspberry Pi with zero knowledge in programming xD
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Start up with hello world.. C or C++..

learn using either vi,vim,nano,gedit and compiler such as tcc, gcc, g++

Pretty simple.. google up and good luck ! smile.gif
satz
post Jan 24 2013, 09:32 PM

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QUOTE(Aeon89 @ Jan 24 2013, 04:46 PM)
thanks, lots to learn, since this would be my first, never done any computing language before (business grad)
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its pretty simple.. you can either google up or post up questions here smile.gif
satz
post Jan 25 2013, 06:02 AM

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QUOTE(C-Fu @ Jan 25 2013, 02:02 AM)
then i definitely recommend you to take up python instead of C if you wanna do more than just installing RaspBMC. much simpler and direct.
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learning c/c++ or assembling language will give him a foundation of basic programming.
From there onwards, there wont be much difference when porting up to java, C,C++...
satz
post Jan 25 2013, 09:05 PM

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QUOTE(C-Fu @ Jan 25 2013, 11:30 AM)
well c/c++ is anything BUT basic.

the language norm for RPi is python anyway, and if he wants to do anything related to GPIO then Python can get him up and going in no time instead of doing the same thing in C, or even mov ax,cx in assembly for that matter
*
well, for me, i felt C/C++ very much easier to customize.
And response rate from sensors are faster. When the code gets huge
with sqlite3 database integration and running simultaneously in
6 different threads, c++ performs faster in ramfs (ram disk).
This is what i felt, it may differ compared to the others.

A small overview.

CODE

//declare headers
#include <iostream>
#include <wiringPi.h>


CODE

//declare which GPIO pins to use
#define sensor_1 27
#define sensor_2 22


CODE

//set up pin mode, either input or output
pinMode(sensor_1,INPUT);
pinMode(sensor_2,INPUT);


CODE

//setup gpio pin numbering
if (wiringPiSetupGpio()) return 0;


CODE

// if yes, continue the code (may place this in loops)
if ( digitalRead(sensor_1))
{

{

satz
post Feb 17 2013, 12:07 PM

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QUOTE(eric_tan @ Feb 16 2013, 04:58 PM)
Finally received mine.... don't even know what should I do with mine....

[attachmentid=3308416]

What do you guys user you Pi for?
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you name it.. smile.gif
satz
post Apr 2 2013, 02:29 PM

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QUOTE(shadow111 @ Apr 2 2013, 02:22 PM)
I'm interested to get one to play around with. Shouldn't you be selling cheaper compare to online new unit?
Btw. Is it safe to get from element14 site? what's the lead time for the delivery if anyone of you buy it before?
Thanks.
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if there is stock, order before 2pm, will recieve next day itself. Gdex.
satz
post Apr 2 2013, 03:29 PM

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QUOTE(shadow111 @ Apr 2 2013, 02:47 PM)
IC.. It's showing as below. It's only available in Sin and UK.. Does this means it's OK to ship to Msia too?
Btw.. what other peripheral that I need to purchase?
Thanks.

RASPBERRY-PI - RPI-B-512-CASED - SBC, RASPBERRY-PI (B) 512MB, CASED
Availability: SG 393 ,  UK 32
Price For: 1 Each
Minimum Order Quantity: 1
Order Multiple Quantity: 1
Unit Price: RM150.00
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as long its in SG, it would be delivered on the next dat itself if no other issues involved.
Ordered huge number of stuffs with them already. (company purpose)

Peripherals, i would not suggest form element14.
Some yeah, depends on your needs.

HDMI- quite cheap - no need for headless. First time set up, YES u need HDMI
Later part can use SSH or vnc- if in case for automation purpose.
Normal media player obviously hdmi is imp.

wireless adapter - get edimax- pretty good. but u need to set up script for autoconnect
(usually it disconnects for no reason) . can be done using crontab

key board mouse depends.

Most important - SD card. get a compatible ones. I did face data corruption issues on sandisk
after 1 month of intense use, intense (write to card almost 3 to 5 times per second)
I noticed SONY card did pretty well.




satz
post Apr 2 2013, 03:59 PM

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QUOTE(shadow111 @ Apr 2 2013, 03:54 PM)
I do have my own HDMI cable and also SANDISK 8GB SDHC..
for power, i can use my S III charger for it, right?
guess I just need to buy the unit without any additional peripheral.. smile.gif
*
yeah, normal samsung chargers would do.. as long 750mah should b fine

i tried powering up my pi with even 450mah, headless. - no issues
runs fine for almost a week, with constant wireless data transmissions
(but only one usb port would work)

even pc usb port would do, again depends.
i already left pi, now trying up with metro ui for my new radio app after blazing radio.

Good luck ! smile.gif


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