Hello,
I'm using since some months an ICM-20602 with success. I store 5 ms of data in the FIFO and I read the FIFO once every 5 ms (upon interrupt). This works perfectly.
I'm now trying to configure an ICM-42688-P to have a higher datarate. I use the same method: record data into FIFO during 2.5 ms (5 ms data overflows the FIFO) and I read it upon interrupt. The watermark is set to fire the interrupt. I use 16-bit data length, accelerometer and gyroscope at 32 kHz. Temperature and timestamps are enabled.
My problem is that I get successfully interrupts every 2.5 ms. Reading COUNTH and COUNTL gives me 0x0500 bytes ready in the FIFO. Reading FIFO_LOST_PKT0 and FIFO_LOST_PKT1 gives me 0 packet lost.
But when I start reading the 0x500 bytes of the FIFO in burst, I get only 0s.
The two attached files show the configuration of registers. Note that I haven't written the default bits in my table, but the default bits respect the datasheet in the code, as suggested by the datasheet.
Do you have any idea why I get only 0s ?