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I made a custom circuit with bno055 it shows i2c address 0x70 is it possible? I used the Arduino i2c scanner. I am not getting any data aswell

nothing else is connected to Arduino nano board as well,

I am using 5v to 3v3 TTL logic level converter board as well

vdd 3v3

11 and 14 not connected to Arduino

enter image description here

I tested with 3v3 esp32 using Arduino i2c scanner, Still, I am getting the same address 0x70, without the converter, above PCB directly connected to esp32

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    \$\begingroup\$ " it shows i2c address 0x70" Where did you get that from? The datasheet of the BNO055 specifies 0x29 or 0x28 (or in HID-I2C: 0x40). As you can see 0x70 is not mentioned. So the answer to "is it possible?" is 'unlikely'. You are probably seeing some other device or you have major communication problems. \$\endgroup\$ – Oldfart Jan 24 at 16:28
  • \$\begingroup\$ @Oldfart what sort of communication problem? \$\endgroup\$ – vassidefuk Jan 24 at 16:37
  • \$\begingroup\$ there are no other devices \$\endgroup\$ – vassidefuk Jan 24 at 16:43
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    \$\begingroup\$ Some level shifters, like from Sparkfun, already have pull-ups on board, both high and low voltage side. In this case you should not add more resistors. Check shifter schematics. In fact, if you want us to stop guessing and actually help you, entire schematics and references to ALL component datasheets would go long way \$\endgroup\$ – Maple Jan 24 at 17:53
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    \$\begingroup\$ You are missing the point. Are there no pullups on 3.3V side at all, or no pull-ups on shifter boards, or no pull-ups on BNO board? Is there only one pair of pull-ups on 5V side, or there is another on shifter board? As I said, without complete picture it is impossible to give meaningful advice. Provide links to the boards you are using and actual connection schematics (without "I am not using this or that" spread all over the comments) \$\endgroup\$ – Maple Jan 24 at 18:18
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No, 0x70 address should not be possible. Make sure pins PS0/PS1 (protocol select) are connected to the ground, to activate I2C protocol.

Then, depending on address selection input COM3 the BNO055 address will be either 0x28 or 0x29. Decide which address you want to use and connect COM3 pin to either GND or 3.3V directly.

Also, depending on I2C API you are using, the addresses might be represented shifted to the left (to make space for RW bit). These APIs will use 0x50 and 0x52 correspondingly. Still no 0x70 in picture.

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  • \$\begingroup\$ IC was in the reset state now it shows 0x28 \$\endgroup\$ – vassidefuk Mar 25 at 11:04

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