AD9915 Clock Stall low/high

Dear all,

In the DS figures 42-45 two modes are illustrated Clock Stall LOW and Clock Stall HIGH. I could not find any information on how can I change it and what is the default setting. Also on the page 38 in the 3rd paragraph it says that serial interface port can be configured as 2-wire (SDIO) and 3-wire (SDIO and SDO) interface AFAIK there is no further information on how to set and what is a default configuration.

Best,

Vyacheslav Li