Yes, there were two different digital I/O cables--and the deck was arranged so that it would lock out recording at 44.1 kHz if you used the S/P-DIF cable, while with the AES/EBU cable you could record at any of the three available sampling rates (32 / 44.1 / 48). (This was back when the RIAA was fomenting huge panic about the possibility that audio CDs could be digitally copied and pirated.)
I accidentally damaged one of these cables; Sony still had replacements back then, costing ~$200 each. But they have long since run out.
The analog input circuitry for this deck is generally a nightmare. It requires very high levels to drive the XLR inputs to full modulation when they're set for line level, while if you set them for mike level, they overload very easily regardless of the record level settings--not very suitable for professional condenser microphones, even the ones that were in common use when this deck was introduced. And do I remember correctly that there's no phantom powering built in?