The signal names and possible routngs suggest that I can synch a 4552 (master) and a 6120 (slave) over RTSI. It probably means using DAQmx with traditional DAQ, but I believe that this is also possible.
I didn't make it clear that I'm talking about Analog In only. I realize that there will be a several sample deterministic delay between the 4552 and the 6120. I can adjust the data to compensate if that becomes a problem.
You can use Traditional DAQ with the 4451 and DAQmx with the 6120 at the same time. Take a look at the example at this link which synchronizes two 445x boards with a common trigger and sample clock.
All you have to do is take out the slave portion of the code and replace it with DAQmx code where the DAQmx Timing VI has the corresponding RTSI line as its sample clock source, and likewise for the DAQmx Trigger VI. Here is an example that synchronizes an E-series (DAQmx) with an Analog Output board in Traditional.
That sounds like it will solve my problem. I'm familiar with the multiple DSA card code already, but not with the 6120 or DAQmx. I guess it's time to learn
