BNO055 failure (no ack)

RE: BNO055 failure (no ack)

Hugo — Thu, 11 Apr 2019 08:07:39 GMT

I made some new test, just removing the two reset components 74LVC1G125. The I2C lines works fine with the PCA9306, even if its datasheet asks a VREF1 to VREF2 voltage difference of at least 0.6V.

RE: BNO055 failure (no ack)

Øyvind — Wed, 03 Apr 2019 13:08:19 GMT

Glad to hear you found the solution!

Best regards,
Øyvind

RE: BNO055 failure (no ack)

Hugo — Wed, 03 Apr 2019 12:57:24 GMT

There is 2 10k resistance on each side of the converter. IOREF is connected to VDD (3v) on PCA10040. So it makes a 5k average resistor on lines.
And VDD was very fine, leds was ok. Just the reset line I didn't check well.

RE: BNO055 failure (no ack)

Hugo — Wed, 03 Apr 2019 12:43:33 GMT

I found the problem: the reset line is also to d2 by lever converter 74LVC1G125.
There is actually 3 of them: one for the reset button, one for d2 reset, and one in the other way for the interruption pin. It's good remove and shortcut them too.

Maybe there is a better way to trick power sypply of the board and avoid all this changes. But doing it work, and makes it not compliant with original arduino.
on the drawing, I inverting "in" and "out", but they just need to be directly connected.
I couldn't post it earlyier, this topic was unreachable.

RE: BNO055 failure (no ack)

Øyvind — Wed, 03 Apr 2019 11:38:28 GMT

[quote user=""]I removed the PCA9306, and 5k pullup should be really fine[/quote]

Have you mounted 5k instead of 10k? 4k7 are usually standard and should be sufficient. Are all SDA and SDL lines connected after PCA9306 removal?

-Øyvind

RE: BNO055 failure (no ack)

Øyvind — Wed, 03 Apr 2019 10:51:53 GMT

Hello,

It's not very clear what you are using. Are you trying to use an Arduino library with our SDK? How did you connect the mma7660?

Are you sure that the BNO055 is powered? Have you measured VDD? Have you tried to debug?

Kind regards,
Øyvind