Apparently, the information you require is (probably) contained within an HP (and possibly Philips) document entitled "Connection of Devices via the MIB/RS232 Interface".
Unfortunately, I have been unable to hound that one down on the Magic Web.
However,
this site may provide a few encouraging clues.
By the way, the reference
book cited in that link (namely, "Interfacing the IBM-PC to Medical Equipment: The Art of Serial Communication" (1995)) is available from Amazon, eBay
et al. I don't have that one myself, but perhaps I'll come across it one day.
Frank has the
manual, but I'm guessing you already have that.
Buena suerte!