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Hi,
sorry for the late response, my computers OS (W10) decided to die last weekend amd I had a lot to do to try to reanimate it and finally I lost it. R.I.P.
With a fresh and clean W10 installation I spend my time to bring my programs back.
I use the P82B715. The circuit is nearlly the same as yours except the diodes.
It works with an IMU that I had here. With three new ones I bought from China it works not. But I didn´t invetigate yet if this is a problem of the I2C extender or a problem of the IMU-modules itself.
I don´t now witch bus speed is used by the program (100 khz or 400 khz). Maybe Sean can say something about that.
Best Regards
Andreas
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it is probably 100khz, the program doesn't set it if I recall, it's set in the kernel parameters and 100khz is probably the default
Maybe you can run the i2c slower, but I think it must be at least 20khz, maybe 40khz if that would help extend range
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Hi Sean,
the extender can handle the "normal" bus speed up to 100 kHz. So this is not the problem. I asked about the bus speed cause I2C allows a "fast" mode up to 400 kHz. This is too fast for the P82B715.
So bus speed is not my problem with the non working IMUs. I didn´t belive that this is the problem cause I have a working IMU with my extender circuit.
Thanks and best regards
Andreas
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I'm pretty sure it's 100khz, but to be sure you could use a scope or logic analyzer. It is normally set in the /boot/config.txt where you can also change it.
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Hi,
it was a problem with the IMUs. I tested now three other ones I ordered from an other source and they work as aspected. So the I2C extender I used can handle the bus speed and with the right IMUs there is then no problem :-)
Best regards
Andreas
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you would have to write a driver for it