资 源 简 介
There are two phases to a communicaTIon cycle with the AD9777. Phase 1 is the instrucTIon cycle, which is the wriTIng of an instrucTIon byte into the AD9777 coincident with the first eight SCLK rising edges. The instruction byte provides the AD9777 serial port controller with information regarding the data transfer cycle, which is Phase 2 of the communication cycle. The Phase 1 instruction byte defines whether the upcom-ing data transfer is read or write, the number of bytes in the data transfer, and the starting register address for the first byte of the data transfer. The first eight SCLK rising edges of each communication cycle are used to write the instruction byte into the AD9777.
