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Timeline for Adding devices makes I2C read 0

Current License: CC BY-SA 3.0

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S Dec 13, 2014 at 21:13 history suggested dda CC BY-SA 3.0
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Dec 13, 2014 at 16:02 review Suggested edits
S Dec 13, 2014 at 21:13
Oct 16, 2014 at 5:36 history tweeted twitter.com/#!/StackArduino/status/522622209123422208
Oct 14, 2014 at 4:08 answer added albator timeline score: 1
May 4, 2014 at 12:11 comment added Ricardo Here it is, the discussion is in this answer to a question of mine. Look at the 3rd comment from the top.
May 4, 2014 at 12:09 comment added Ricardo Somebody else said that it's easier to ship the modules with the pullups and then remove some of them if you combine several modules.
May 4, 2014 at 12:08 comment added Ricardo Well, I was just guessing. As I said, without a scope, there's no way of knowing what's going on. But I read somewhere that each I2C module comes with its own set of pullups. Then, if you place too many of them on a bus, their resistance will divide up, changing the optimal pullup value. So, someone suggested that the modules should come without the pullups, so that one would calculate the optimal pullup resistance of the set of modules and solder it up in one of them (closer to the master I guess).
May 4, 2014 at 8:53 comment added Dr Coconut @Ricardo unforunately, I'm in high school and don't have access to a scope. can I ask how removing a set of pullups might resolve the issue?
May 3, 2014 at 17:41 comment added Ricardo Another guess is that maybe you should remove one set of pullups from one of the boards. But that would probably damage it, so think carefully about it.
May 3, 2014 at 17:39 comment added Ricardo The best way to diagnose I2C problems is to look at the signals with a scope. Then you can see whether the slaves are acknowledging the master's commands, check each sensor address and all. Can you do that and post the shot? Also, schematics would help a lot.
May 3, 2014 at 16:35 review First posts
May 3, 2014 at 16:53
May 3, 2014 at 16:12 history asked Dr Coconut CC BY-SA 3.0