bypass mode not working on 9250

We recently moved a prototype design from the 9150 to the 9250, and I'm in the process of updating our (home-brew) driver code to talk to the new chip.

One problem is that I can't talk to the magnetometer in the 9250s. As far as I can tell from the data sheet, there should be an AK8963 at address 0x0c on the internal I2C bus. But when I put the 9250 into bypass mode, the AK8963 isn't there.

I think that means either the magnetometer isn't working (unlikely) or that the 9250 isn't actually going into bypass mode. The rest of the 9250 seems to be working, however.

Here's what we're doing to put the "old" 9150 into bypass mode:

1. Clear the I2C_MST_EN bit (0x20) of the USER_CTRL register (106)
2. Set the BYPASS_EN bit (0x02) of the INT_PIN_CFG register (55)

Should these same steps work on the 9250 as well? Are there any other initializations that should be performed before using bypass mode?

If anyone else has worked through a similar problem, I'd be interested to hear about what you did.

Thanks,

Andy