  We present a large family of Spin(p,q)-valued discrete spectral problems. The
associated discrete nets generated by the so called Sym-Tafel formula are
circular nets (i.e., all elementary quadrilaterals are inscribed into circles).
These nets are discrete analogues of smooth multidimensional immersions in R^m
including isothermic surfaces, Guichard nets, and some other families of
orthogonal nets.
