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sj_h1
(@sj_h1)
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Joined: 2 months ago
Posts: 27
2020-10-01 9:37 pm  

I have a project that I would like to use I2C over a 10 meter distance. This will actually connect several slave Arduinos (probably Nano) to a master Arduino (probably an Uno).These are not daisy chained but all slaves connect to the master no more than 10 meters away. I have heard that the I2C is really only reliable to about 1 meter. I saw on the old patreon number 1 that there was a chip to do that but he never says what it is. Anybody know?


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DroneBot Workshop
(@dronebot-workshop)
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Joined: 1 year ago
Posts: 652
2020-10-01 10:15 pm  

It was the Texas Instruments P82B715 Steve, but I had a few difficulties getting it to work. 

I also have seen a module that uses it, you might have better luck with that.

And Sparkfun makes a module that allows you to use Ethernet cables to extend I2C.

Hope that helps!

😎

Bill

 

"Never trust a computer you can’t throw out a window." — Steve Wozniak


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sj_h1
(@sj_h1)
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Posts: 27
2020-10-02 12:09 am  

I found SparkFun Differential I2C Breakout - PCA9615 (Qwiic) I think this is it. Its seems about right, but how would I attach multiple slave Nanos Do I need one for every slave on the master?

 


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DroneBot Workshop
(@dronebot-workshop)
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2020-10-02 12:21 am  
Posted by: @sj_h1

how would I attach multiple slave Nanos Do I need one for every slave on the master?

No, you only need two (I'm assuming that the slaves are all in the same physical location), on the "slave side" you just treat the I2C bus output as you would any I2C bus connection.

However, if your slaves are in different locations (like when you fire a dozen rockets at once) then I'd suggest using an I2C multiplexer like the TCA9548A to split the I2C bus into several independent I2C busses.  Then you'd need an extender on both ends of each line (this is getting expensive LOL).

Hope that helps!

😎

Bill

"Never trust a computer you can’t throw out a window." — Steve Wozniak


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sj_h1
(@sj_h1)
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Joined: 2 months ago
Posts: 27
2020-10-02 12:26 am  

@dronebot-workshop That was a big help. I was going to have a I2C line to each pad but I never considered just one main line out connecting the pads (slaves) together. Thanks


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