So I've flown this BMA180 on countless flights before, but after re-wiring it to a breadboard for re-installation onto the MWC, I'm having no success.
I'm using 1.7 for this since 1.8 hasn't been very reliable for me.
When the BMA180 is plugged into the I2C line, my cycle times range from 6k to 30k to -12k, or freeze altogether... I used to get 4k with this chip before I rewired it.
The GUI will behave normaly if only the WMP is on the I2C line. Adding the ACC causes the graph to show no changes, even on the gyro lines.
Before adding BMA180:
Before adding BMA180
After adding it:
After adding bma180
So it seems that the I2C line is being poisoned by something related to that ACC. But I'm not sure what it could be..? I've checked everything very thoroughly (so I think) and I've found no errors.
What am I missing?
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The BMA180 is anchored in place on this breadboard with 2 header pins. All connection bridging is done up on top where it can be seen.
I've used magnet wire to make my connections because it's light weight and flexible. All the ends were dremeled clean to expose the copper, then fluxed, then soldered.
All multi-wire junctions were fluxed again before being soldered, to ensure no cold joints.
Continuity was tested on each little wire before I added it to the board.
I've tested for shortcuts by testing the leads that enter the I2C line--none offer 0 resistance, so I'm confident that I've not crossed wires somewhere.
Voltage powering the board was measured at 3.30v--I'm using Jussi's shield, which has a regulator on board.
Internal pullups are //disabled in code.
Here are the diagrams I've followed to set this chip up:
Any insight here is greatly appreciated! I'm wasting what's left of the flying season with this spag
The BMA180 could be damaged/dead, so I'd suggest you purchase another one and try again. Be aware that chips can be gravely harmed if poor static control methods are used during soldering, so review your soldering tools and work bench for such issues.
Also, instead of hard mounting the BMA180 BOB onto the perfboard with the two header pins, I suggest you remove the pins and soft mount it on foam or gel pad. Your wires can be routed so that they are shorter (yet still flexible) so that they do not contribute any vibrations into the floating BOB assembly.
Is the behavior I describe symptomatic of a damaged acc?
I've never installed a bad BMA180 to see what happens, so I cannot confirm anything.
If you have an o-scope you could check the I2C buss to see what it is doing with the BMA180 installed. Also, if your scope shows that the PowerPin cycles when the BMA180 is installed then it is surely corrupting the I2C buss.
Sadly, I don't have such a contraption... never even seen one! Isn't there a way to make one using a sound card out of a computer, some how? Or was that some other gadget I'm thinking of?
Just as a parting comment, there is still hope that the problem is in the build. That is to say, you've shown everything you've done to the BOB. However, it needs to be connected to your Arduino and that wiring is suspect too. So check ALL your wiring again. Good luck!
Good question though!