ADIS16209 - CALIBRATION REGISTERS

Hi,

I building digital inclinometer with ADIS16209 and I want set calibration offset - using i.e. ROT_NULL.

For example:

I have to set -10 or -100 (DEC) and I can't set it.

If I send 0x01A00 | 0x8000 | 0x000A = 0x9A0A

and I set 10 (DEC) in ROT_NULL register.

But how I need to calculate value for twos complement and send to ROT_NULL register for offset negative -10 (DEC) ?

If I send 0x9BFC -> I get -1024 (DEC) offset

If I send 0x9B04 -> I get +1024 (DEC) offset

How I can set +1000 (DEC) or -1000 (DEC)

 

Maybe its simple but not for me. Can someone help answer me for this issue?