07-02-2019 06:40 PM
Hi,
I'm new to this forum and hope to get some help with a problem in my design.
I might be force to share a GPIO of my microcontroller for two purposes:
(A) Receive Interrupt from BMI160
(B) Measure a voltage through a voltage divider with very high impedance
I have attached snippets from the schematic. "M_VPRE" and "INT_BMI160" are connected to the same GPIO.
When application (A) is active, VPRE is expected to be close to GND.
When application (B) is active, there is no data communication from BMI160.
To my current understanding it should be possible if INT1 is/can be set to be high-Z when application A) is not running. Unfortunately the datasheet is quite lenghty and I was not able to find that info with quite a lot searches.
I found that in the INT_OUT_CTRL register I can set int1_output_en to zero. Will this set the pin to high-z?
Thanks for your help,
Johannes
Solved! Go to Solution.
07-03-2019 09:46 AM
07-08-2019 10:40 AM
Thanks, sorry for my late reply, I had notifications turned off.
What is the behavior after POR? I can see that intx_od will be push-pull but intx_output_en will be 0=disabled.
What happens to the pin in "disabled" state, is it High-Z?
Also, you wrote
Since you have a pull-down resistor already, set the interrupt lvl to 1, so the interrupt pin will be VDDIO when active, HI-Z otherwise.
I don't think this will work, open drain requires a pull-up, it can't actively drive a pull-down up to VDDIO.
BR Johannes
07-08-2019 01:49 PM
@jmuellers wrote:
Thanks, sorry for my late reply, I had notifications turned off.
Email notification is unfortunately not yet enabled. We have no estimations when this feature will be enabled on the community yet. 😟
@jmuellers wrote:I don't think this will work, open drain requires a pull-up, it can't actively drive a pull-down up to VDDIO.
Open-drain typically uses a pull-up resistor and active low level, but this is not a general rule. Our parts can also be configured to use a pull-down resistor and active high level.
@jmuellers wrote:What is the behavior after POR? I can see that intx_od will be push-pull but intx_output_en will be 0=disabled.
What happens to the pin in "disabled" state, is it High-Z?
yes
07-08-2019 02:27 PM
Thank you, I'm confident I understood and can solve my problem now.
Seeing how fast it was resolved here, I wish I had more problems with Bosch products, and less with others... 😁
Cheers
Johannes