Increment Registers

The increment value is stored in three registers making up a 20-bit word. In order of LSB to MSB, they are:

The increment registers are readable and writable and are double-buffered to allow value changes to be made without first disabling the NCO module.

When the NCO module is enabled, the NCOxINCU and NCOxINCH registers will be written first, then the NCOxINCL register. Writing to the NCOxINCL register initiates the increment buffer registers to be loaded simultaneously on the second rising edge of the NCO_clk signal.

When the NCO module is disabled, the increment buffers are loaded immediately after a write to the increment registers.
Important: The increment buffer registers are not user-accessible.