In need for some advice Arduino board

Post by **Digit** » Sun Oct 04, 2009 11:42 pm

Hi,

While exploring the capabilities of the Arduino board i bought recently i could really need some advice on whether what i am doing is ok or not.
Since i'm a complete nitwit in this area, i would really appreciate some of the guru's to have a look at it...

The Arduino board has 14 x Digital I/O, so i thought i'd buy me a few bistable (latching is the right word i think) relays and attach those to my Arduino. For now i have 1 of those relays connected, just to try it out.

These are the relays i use.

In the end i want to make some sort of relay board with a couple (5 or more) of relays to switch a number of devices i have in my meter box; mostly interfaces like GSM modem, PBX, etc etc; the usual stuff you'll find in 'our' homes. I thought building this with 2 XBee modules, an Arduino and a couple of relays is a cool [8D] way to create my own wireless relay board.

So now i've got 1 relay connected to 2 Digital I/O ports. 1 DIO for switching on, 1 DIO for switching off, since the relay has a coil for each state. I wrote a little Arduino sketch that will give a 10 ms pulse to one of the DIO ports on a command received by XBee which results in switching the relay into the desired state. It is working (as in: i hear the relay making clicking sounds), but:

Is this the best way to connect this kind of relays to my Arduino?
Is there a way to only use 1 DIO for switching this kind of relay somehow?

<hr noshade size="1">Robert
http://www.hekkers.net Digit's Online Home.

Post by **bprosman** » Tue Oct 06, 2009 10:33 pm

Trying to do tht with one line will require extra electronics , downside as well is that it is harder to get back into a defined state (you need to start working with pulselengths), in the current situation you always know which pin to toggle to get to an off or on condition. If you run out of I/O lines I would suggest to extend these for instance by using an I2C IC like a PCF8574.

Regards, Bram

Post by **Digit** » Tue Oct 06, 2009 11:28 pm

Thanks for the tip, i'll have a look at it!

<hr noshade size="1">Robert
http://www.hekkers.net Digit's Online Home.

Post by **bprosman** » Wed Oct 07, 2009 12:36 am

http://www.arduino.nu/download/Arduino% ... 0%20NL.pdf

Pagina 32.

Groeten, Bram

Post by **Digit** » Wed Oct 07, 2009 12:49 am

Thanks again!
ROC A12 is in bicycle range for me, i wonder if they accept me as a student to attend some lessons

<hr noshade size="1">Robert
http://www.hekkers.net Digit's Online Home.