I have a TenTec Orion Transceiver with an bad control board that has parts that are unavailable. The multiple boards all have control input using the Allegro A6810 for serial control. Serial data is input at least 25ns before the clock pulse is send and held for 25ns. Required clock pulse width is 50ns. Data is clocked in shift register style and then 100ns after the last clock data is strobed into the latches. Data sheet says these times are representative of a 10 MHz clock. Assuming clock can be slower and there is no rush on these controls.
What is the best way to control these boards with the Arduino? Bit banging or one of the serial modes?
Just want to control some of the functions in an alternate use.