I don’t know what an SPD-S is but if it’s electronic and makes a noise you can connect it to the A/D Input on the back panel of the MOTIF XF.

Sampling guides need not be specific to any one device. What you need to decide is what about an SPD-S is of interest to sample.
For example, you could perform on it and capture that performance... like recording a song. Or you could record single “one shot” events that you later use to construct a performance once the individual ‘one shots’ are assembled...

What you need to know is the A/D Input can accept one mono or stereo input... you would set the MIC/LINE = LINE Input
[UTILITY] > [F2] I/O > Set MIC/LINE = LINE

Sampling can be done to a Voice, you can also sample in the Sequencer Mode...

Here are some documents to help:

Sampling in the Sequencer

Thanks! Yes, the SPD-S is a 9-zone drum pad, a vintage electronic drum pad. Thanks again for the info!