An optical Digital Signal Processor (DSP) circuit includes a digital core configured to implement digital signal processing functionality and configured to operate at a plurality of baud rates including a full baud rate and a half-baud rate; and an analog interface including a Digital-to-Analog Converter (DAC) section and an Analog-to-Digital Converter (ADC) section, wherein the analog interface is connected to the digital core and is configured to operate at the full baud rate when the digital core is configured to operate at any of the plurality of baud rates.