Notifications
Clear all

I2C bus wiring  

  RSS

Spyder
(@spyder)
Prominent Member
Joined: 1 year ago
Posts: 780
2019-11-29 3:05 pm  

How is everybody handling the I2C connections ?

What I mean is, you're going to have 5, 10, maybe 15 I2C devices all tied together, so how are you handling that ?

A bus strip ? An octopus ? Etc


Quote
Pugwash
(@pugwash)
Prominent Member
Joined: 1 year ago
Posts: 970
2019-11-29 4:35 pm  
Posted by: @spyder

How is everybody handling the I2C connections ?

What I mean is, you're going to have 5, 10, maybe 15 I2C devices all tied together, so how are you handling that ?

A bus strip ? An octopus ? Etc

A two-wire bus, one wire for SDA and the other for SCL!


ReplyQuote
robotBuilder
(@robotbuilder)
Reputable Member
Joined: 1 year ago
Posts: 467
2019-11-29 5:48 pm  
Posted by: @spyder

How is everybody handling the I2C connections ?

Badly!

Had been trying to read data from a HMC6883L magnetometer module without success.  The compile just kept giving errors not being able to find certain methods in the HMC6883L class.  Tried downloading and installing using the library to the IDE using methods explained but nothing worked.  Tried a simpler example without the HMC6883L class involved I found here,
https://www.electronoobs.com/eng_arduino_tut77.php
the first example was supposed to just print to the Arduino IDE monitor, still no success.
So I ran this scanner,
https://playground.arduino.cc/Main/I2cScanner/
and it came up with a different address to the example code?
Anyway I plugged the module back into the board but misaligned the pins. The module became very hot and I think I have destroyed the module and maybe even the Uno!! So that is the end of that!


ReplyQuote
Chip
 Chip
(@chip)
Trusted Member
Joined: 9 months ago
Posts: 83
2019-11-29 6:56 pm  
Posted by: @spyder

How is everybody handling the I2C connections ?

What I mean is, you're going to have 5, 10, maybe 15 I2C devices all tied together, so how are you handling that ?

A bus strip ? An octopus ? Etc

Here is my I2C bus , its not pretty but it works. If you have more devices you could just make the strip longer and use jumper wires on top and feed your I2C devices on the bottom. So only one green and one yellow wire goes back to my arduino ( SDA & SCL).

I2C BUS

Hope this helps.


ReplyQuote
Chip
 Chip
(@chip)
Trusted Member
Joined: 9 months ago
Posts: 83
2019-11-29 7:11 pm  
Posted by: @casey

The module became very hot and I think I have destroyed the module and maybe even the Uno!! So that is the end of that!

Oh man, I hate to hear that. Seems to me maybe the 5v or 3.3v may have been backward with ground on the device because the sda and scl being backwards I don't think would have made it get hot. If still have your 5.5v and 3.3v on your UNO then more than likely you did not destroy it.

Also check this out,

https://www.sparkfun.com/products/retired/10530

hmc5883lcomment
This post was modified 7 months ago 3 times by Chip

ReplyQuote
Chip
 Chip
(@chip)
Trusted Member
Joined: 9 months ago
Posts: 83
2019-11-29 7:15 pm  
Posted by: @casey

So I ran this scanner,
https://playground.arduino.cc/Main/I2cScanner/
and it came up with a different address to the example code?

look at this list and see what device it might have detected.

https://learn.adafruit.com/i2c-addresses/the-list


ReplyQuote
robotBuilder
(@robotbuilder)
Reputable Member
Joined: 1 year ago
Posts: 467
2019-11-29 8:23 pm  

@Chip

The scanner program returned an address of 0x30
No big deal. Will order another module and try again next weekend.

 

This post was modified 7 months ago by robotBuilder

ReplyQuote
Spyder
(@spyder)
Prominent Member
Joined: 1 year ago
Posts: 780
2019-11-30 3:34 am  

I had an item the other day that read an address of 0x30

Can't remember what it was tho. I should make a list. But that's too much like organizashun, and I can't even spell that word

My thought on the connector was a screw type terminal strip, but I wanted to see if anybody thought that was a stupid idea first


ReplyQuote
Spyder
(@spyder)
Prominent Member
Joined: 1 year ago
Posts: 780
2019-11-30 3:35 am  

@casey

I had an item the other day that read an address of 0x30

Can't remember what it was tho. I should make a list. But that's too much like organizashun, and I can't even spell that word

My thought on the connector was a screw type terminal strip, but I wanted to see if anybody thought that was a stupid idea first


ReplyQuote
Duce robot
(@duce-robot)
Reputable Member
Joined: 1 year ago
Posts: 466
2019-11-30 8:55 am  

With about 50 breadboards with a thousand wires running down a million rabbit holes lol but that's duce! A birds nest .


ReplyQuote
Pugwash
(@pugwash)
Prominent Member
Joined: 1 year ago
Posts: 970
2019-11-30 11:32 am  

@spyder

Almost fried a BME280 by wiring the wrong way around.

I guess a Shottky diode on the ground lead to the I2C module, might prevent further cooking sessions!


ReplyQuote