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1  Community / Local Groups / Re: Any fans in Singapore? on: December 28, 2011, 09:44:31 pm
Hey guys,

Sorry I have distracted lately (got obsessed by 3d printing) and havent been checking the forums.

BillHo is right, there are those 2 suppliers. Not sure if any more sprang up tho.

Kopiohh, yes I have gotten stuff from both Robots R Us and SgBotics. Both are very customer oriented. Sometimes you might have a little better offer from one or the other, so it pays to check both prices before you buy.

Intially I bought 3 Unos because I wanted to make sure I could start with something reliable. But soon I found that making your own boards is much easier than it sounds, waaaay cheaper, and much more fun/satisfying. About the biggest cost would be the Atmega, and that is about 6 bucks? I think you can make your own extra boards for $8 to 10 easily.

After u get your first board, had so much fun that you want to make more stand alones, I can point u in the right direction.

Keff
2  Topics / Home Automation and Networked Objects / Re: Iphone control program over network: someone interested? on: December 28, 2011, 09:25:07 pm
Hi guys, I've been distracted by 3D printing the last few months and was pleased to see this thread today.

I made a working system though I used it to control my lights only. I used an ethernet shield and wifi to control it from my iPhone with HTML. The system is made up of nodes using RF and IR to communicate. I made the control home page as simple as possible (definitely no pics) so I could control quite a number of lights with just an Atmega 328.

I also made my own control (using Atmega328) relay boards for the control of the 230V lights and a, mixture of RF and IR control boards. My basic design premise was to make it as simple, robust and low cost as possible, kind of like the WW2 Russian T-34 tank. (IMHO for the more mundane tasks like light and appliance control, Zigbees would be a waste).

I would be happy to help develop it into a fuller system if anybody is interested.

Keff in Singapore

3  Using Arduino / Microcontrollers / Re: Programing Atmega without uno in PCB on: April 02, 2011, 10:23:54 pm
Hi Drew,

I tried using your instructions, but couldn't make it work. I also tried other variations / permutations:
- connecting the Vcc
- connecting Gnd to Reset on the Uno,
but, but all no luck.

Have you tested on Uno yet? On the tutorials page http://arduino.cc/en/Tutorial/ArduinoToBreadboard there was a note that: "Note that these techniques only work with the Arduino Duemilanove w/ an ATmega328, not the Arduino Uno (or older Arduino boards w/ an ATmega168)." . So it appears that the different boards have quite a different make up.

Thanx
K
4  Topics / Education and Teaching / Re: What's your opinion on spending $50 on your kids education? on: April 02, 2011, 07:44:26 pm
Quote
John, Let's continue some conversation about teaching Teachers and Parents how to enable young people to encounter Arduino, STEM and technology in general in a positive way. Any other opinions, anyone??

Hi Terry,

I too am interested in this subject. I come from Singapore, and there isn't much of a culture of tinkering here. So while there are trained engineers etc who are comfortable with handling circuit boards etc, most people are quite intimidated by exposed electronics parts.  I don't know if this is the same in other parts of the world ?

My impression is that this intimidation factor is the single biggest obstacle to learning electronics. My first encounter with electronics was with circuit diagrams and current and resistor value calculations. This can be daunting to all but the most determined student. For me, I found it so dry and simply just could not go on and left it for about a decade. It was only when I discovered the wonderful world of Arduino 4 months ago that I really got my hands dirty. And this comes to a person who I think is reasonably technically inclined (I am an architect. No, not the software kind, the bricks and mortar kind).

I got into Arduino because I wanted to build my own home automation system. Now that I have gotten the backbone of my HA system running, I have come to think that it would be an excellent educational tool. This is because simple functions can easily be broken down and demonstrated.

My thoughts is that to remove the intimidation factor, a lesson plan can move from the outside in; meaning the teacher can demonstrate the function (eg. using relay to switch off light), then peel back the skin and reveal the electronics working (eg. remove the relay and show the circuit doesnt work anymore). Later tweaking the programming can be demonstrated, and students introduced to the programming environment / IDE. Lastly circuit can be rebuilt on a circuit board, and students challenged with some creation of their own.

What do you ( and any other reader ) think ?

Keff in Sg

5  Community / Exhibition / Gallery / Re: Animated Paper - Flock of Origami Doves on: April 01, 2011, 09:28:37 am
This is really nice !

Thanks for putting it up.

K
6  Using Arduino / Networking, Protocols, and Devices / Re: ENC28J60, forgive me on: March 31, 2011, 09:28:10 pm
Oops, sorry.

You're an angel all the same !

K
7  Using Arduino / Networking, Protocols, and Devices / Re: ENC28J60, forgive me on: March 30, 2011, 09:41:27 pm
There is a somewhat related topic where an angel in Argentina is writing some mods for the ENC28J60 so we can use the common ethernet shield library. See here http://arduino.cc/forum/index.php/topic,56057.0.html

I'm waiting for my ENC28J60 shield to arrive. Then I will certainly try out the new library.

K
8  Development / Other Software Development / Re: Implementation for Microchip ENC28J60 Ethernet controller on: March 26, 2011, 09:36:34 pm
Hi alvarojusten,

This is fantastic news !

I am sure there are lots of people out there who are eagerly waiting your library. I just wanted to send you encouragement !!!

Cheers from Sg,
Keff
9  Community / Exhibition / Gallery / Re: My Arduino Web Server on: February 15, 2011, 10:57:19 am
Hi Physics-Dude,

There are multiple webpages and there is even a bitmap file in the webpage. But I don't see any of this code in the .pde. Maybe the code you placed on the website is for another page?

Cheers,
K
10  Community / Local Groups / Re: Any fans in Singapore? on: February 14, 2011, 07:53:23 pm
Thanks for starting the Arduino Users Map Mowcius !

After fiddling a bit I managed to place myself on it. It might be helpful for noobs like me if you could add a few instructions like:
  • Sign in using Gmail account
  • Inserted a Placemap
  • Change the default Placemap avatar to the "outline-of-person" avatar



Cheers,
K
11  Community / Local Groups / Any fans in Singapore? on: February 14, 2011, 08:25:44 am
Hi fans in Singapore,

I'm sure there are many of us here. Msg me, it would be nice to meet up and share our gizmos and projects over kopi and kaya toast.

Msg lah, don't shy.

Keff
12  Forum 2005-2010 (read only) / Interfacing / Re: Long-term reliability of Wiznet-based Ethernet? on: January 17, 2011, 10:39:52 pm
Hi Westfw,

Quote
Issued a "send packet" command and not seen a "transmission complete" back within 5 seconds ?  Reset the interface!

Sorry am a real noobie. How do I "request a packet" from the Wiznet 5100? Please could you send a few lines of code. Yes I am that new to Arduino !

Thanxxxx

Kevin
13  Forum 2005-2010 (read only) / Interfacing / Re: Low range on 433Mhz RF link kit on: December 26, 2010, 09:24:29 am
Hi Gents,

I am a noobie, but am currently fiddling around with the RF Links and have noticed some things that are quite illuminating (to me at least). Maybe it might helpful to you.

I am using 434Mhz RF Links, and 17cm antennae where applicable. For data being sent over RF, I am sending about 10 lines of text of about 9 letters in each line:



EFFECT OF RF TRANSMISSION RATE

at 5cm separation between transmitter and receiver, no antennae for both transmitter and receiver.

2000 BPS: 30 % (the 10 lines of code totally correct)
4000 BPS: 40 %
5000 BPS: 60 %
6000 BPS: 40 %
6000 BPS: 20 %



EFFECT OF ANTENNAE

5000 bps rate selected as above.

Separation: 5cm
Receiver: No Antenna
Transmitter: No Antenna
Reliablity: 60 % (the 10 lines of code totally correct)

Separation: 50cm
Receiver: No Antenna
Transmitter: No Antenna
Reliablity: 30 %

Separation: 300cm (3m)
Receiver: No Antenna
Transmitter: No Antenna
Reliablity: not tested, but probably very low

Separation: 50cm
Receiver: With Antenna
Transmitter: No Antenna
Reliablity: 95 % (the 10 lines of code totally correct)

Separation: 50cm
Receiver: With Antenna
Transmitter: With Antenna
Reliablity: 0 % (the transmitter probably overwhelms the receiver)

Separation: 300cm
Receiver: With Antenna
Transmitter: No Antenna
Reliablity: 80 %

Separation: 300cm
Receiver: With Antenna
Transmitter: With Antenna
Reliablity: 95 %



Sorry I am not an engineer, so I can only make some rough guesses on what I am seeing:
  • Looks like the RF Bit Rate has to be chosen with the kind of code in the sketch? By this I mean that if the code is heavy the loop will take longer to run, so the loop cycle is longer. Whether a higher or lower bit rate is beneficial to my code I can't tell. I had to use trial and error.
  • The antenna has a BIG effect on the reliability of the communication. Unfortunately I again can't pin point specifics. It looks like a case by case basis for each transmitter / receiver pair?

Maybe a more RF savvy guy can shed more insight into this?

K in Sg
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