BMA456 offset compensation

[Andy_253]

Hi,

I use the BMA456 sensor.

I would like to use the API bma4_perform_accel_foc, for calculating the foc for all 3 axis - x,y,z.

(I got a code from git hub)

The API recieves the struct : bma4_accel_foc_g_value.

I thought to declare - const struct bma4_accel_foc_g_value accel_g_value = {1, 1, 1, 0},  so all three axis will be calculated, but in the API code I see the following condition :

if (((ABS(accel_g_value->x) + ABS(accel_g_value->y) + ABS(accel_g_value->z)) == 1) &&
((accel_g_value->sign == 1) || (accel_g_value->sign == 0)))

which makes me think I should call one axis at a time (also in related APIs  it seems like that).

but if so - will it be saved corrctly at the NVM? won't each call run over the previous values? 

I don't understand what is the proper input to the accel_g_value

Thanks in advance,

[Andy_253]

Hi BSTRobin,

I tested the FOC with default range(4g) and accel_g_value are {1, 0, 0, 1}

But after FOC, the acc.x value didn't reach to '0'.

I don't think that the purpose of FOC is to make acc value to '0'. It can find the axis of gravity and make it to 8192. Am I correct?

I added some debug message in perform_accel_foc function as below picture.

And then I got a debug message as below.

Do you think, the FOC function working well on my device?

I'd like to know your opinion. 

Best Regards,

Andy

[Andy_253]

Hi BSTRobin,

Could you please reply the my previous question?

I'm waiting for your answer.

Best Regards,

Andy

[BSTRobin]

Hello Andy_253，

Let us to further check and give you feedback later.

[BSTRobin · Accepted solution]

Hello Andy_253，

From your log data, FOC run well on your side.

For your test, X axis should be close to 8192 after FOC, not should be 0.

[Andy_253]

Thanks for your confirmation.

Best Regards,

Andy