Arduino + Several SMBus Sensors

Hello everyone,

I am new to the Arduino's World and to this Forum. I have been researching components for my bachelor thesis and I was glad to find out about Arduino, which looks like the best way to go.

I am considering to make several MLX IR sensor slaves to a standard USB arduino board (they use the SMBus Protocol, hence I will be dealing with the Wire library) but my question is: how many sensors can I hook up? I understand that pins 4 and 5 are already supporting the I2C protocol, but can I use somehow the other digital pins alike?

I'd appreciate if someone could shed some light on this matter. Very Best, Marco

The number of devices you can set up does as far as i understand it, depend on the possibility for giving each device a unique address.

Here are a couple of links with Arduino + smbus stuff:

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1214872633

http://www.homebrewtalk.com/f51/arduino-2wire-smbus-digital-thermometer-104974/

Thank you MikMo!

I have read those links, and my main concern is that the arduino has two pins (4&5) specifically for the I2C protocol, and I can't understand if these guys are using them or other digital pins. They all connect 1 sensor, while I need to connect several.

Very Best and Thanks a lot for the help, M

I2C and therefor also SMbus is i a bus. You connect serveral units in a chain to the same two Arduino pins, thats why each unit (sensor) neds a unique address.

MikMo,

Thanks a lot! Now all makes sense! :)

Best, M