After writing the default (datasheet) value to the control registers of the IMU and performing a "precision autonull" (30s), I read the following control and status regs and obtain two strange values:
:3FEC product ID, OK
:87DB applied voltage, OK
:0034 FLASH_CNT, OK
:0000 ALM_CTRL, OK
:0E00 GPIO_CTRL (default: 0x0000) ***DIFFERS FROM DEFAULT VALUE***
:0006 MSC_CTRL, OK
:0001 SMPL_PRD, OK
:0402 SENS_AVG, OK
:0000 SLP_CNT, OK
:0010 DIAG_STAT Status: ***SENSOR OVERRANGE***
What does this means?
I suppose the GPIO_CTRL value is a minor issue (since I don't need the GPIOs, only use DIO1 for "fresh data" signaling).
But the DIAG_STAT worries me, since the IMU is quiet.
SPI comm is working reliably.
BTW, there's a little errata in the datasheet (rev.D), at page 9 (backup to flash); where it says: "DIN = 0xBE04", it must be: "DIN = 0xBE08" .
Sebastian E. Garcia
TA - Electronics Dept