BMM 150 Reg 0x5D

[Migrant_worker]

HI,

I found in the API routine library that the BMM150 will read registers such as 0x5D and 0x5E when it is initialized,

1.Aren't these registers reserved?

2.What is the significance of reading these registers?

3.Why do I always read 0x00?

[BSTRobin]

Hi Migrant_worker,

We will check and give you feedback later.

[BSTRobin · Accepted solution]

Hi Migrant_worker,

For questions #1 and #2: As indicated in the datasheet, reserved registers are read-only where default value cannot be guaranteed. This is because these registers contain individual sensor-specific values, written into the memory during manufacturing process (see chapter 4.5).

For question #3: The values of trimming registers inside BMM150 are unique for each sensor. Since the trim registers cannot be modified after production, it is expected than one sensor should always return the same trim register values. However different sensors may contain different trim value register values.