The AD9832 has a standard serial in

The AD9832 has a standard serial interface that allows the part to interface directly with several microprocessors. The device uses an external serial clock to write the data/control information into the device. The serial clock can have a frequency of 20 MHz maximum. The serial clock can be continuous, or it can idle high or low between write operations. When data/control information is being written to the AD9832, FSYNC is taken low and held low while the 16 bits of data are being written into the AD9832. The FSYNC signal frames the 16 bits of information being loaded into the AD9832.