TMAG5273: Handling of the Result Buffer and the Content of the CONV_STATUS Register.

Heinz Hornung

Part Number: TMAG5273

Tool/software:

Dear TI Specialists,

I'm a bit uncertain about how conversion results are updated. I plan to read 16 bit results with the "1 byte read" command). I assume

1.) Even if a conversion is in progress, I can read the result registers (for example X_MSB_RESULT and X_LSB_RESULT) and always get valid data (at least after the first conversion).
Especially, it is not possible to read the MSB of conversion "a" and the LSB of conversion "a+1" with a single I2C read access.
This is also true for averaging (for example 32 values).

2.) The CONV_STATUS register (offset 0x18) will be updated together with the result registers. So I can rely on the SET_COUNT to indicate the last conversion.

So, I could do the following:

a) Configure T, X, Y, and Z
b) Configure an average of 32
c) Start continuous measurement mode

Loop:
d) Read all results with a single I2C burst
e) check if SET_COUNT has changed -> if so, store the data
f) jump Loop

BTW: When is the bit "RESULT_STATUS" reset? Automatically when the result buffer is read?

Thanks a lot and all the best,

Heinz

10 months ago

0 Alicia Rosenberger 10 months ago

TI__Genius 14220 points

Hi Heinz,

Thank you for posting to the Sensors forum!

1. If a conversion is in progress, you can read the result registers and read back some data value.

2. The CONV_STATUS register gets updated automatically with the result registers along with the "RESULT_STATUS" bit. The way it'll work is once a conversion is triggered the device will then read the magnetic field and update the result registers and the CONV_STATUS register (which includes the SET_COUNT bit and the RESULT_STATUS bit).

Another option that you can utilize with continuous conversion mode is the result interrupt function which uses the INT pin to signal when a conversion is ready to be read.

Best,

~Alicia