Hi there. I am a final year student and i am supposed to design a circuit whereby the system is to transmit a 1mhz frequency into the ground in order to measure whether oil is available. The system uses a Siemens c167 microcontroller, a DDS chip (AD 9834) and a multiplier (AD835).The DDS chip is supposed to give out a frequency of 0.998Mhz which will be mixed with the 1Mhz and the difference of 2khz is obtained from the multiplier. the multiplier is then connected to the microcontroller. the problem i am having is to figure out how to connect the microcontroller to the DDS chip which in turn is connected to the multiplier. The multiplier must then be connected to the microcontroller to get the output results. This connection has to be done by serial interfacing. It would be of great help if anyone can help to figure out which pins of the microcontroller should i use to connect to the chips and if any extra components are needed. thanks. Need help urgently as time is running short. Cheers