HMC625BLP5E Pinout Connections

Hi,

In reading the datasheet for the HMC625, there is a bit of vague information.  If I plan on using the SPI interface only to control the gain, is it possible to leave D0-D6 unconnected?  Are there internal pullups or pulldowns on any of these signals?

Also can I leave PUP1 and PUP2 unconnected?

Thank you,

Will