All of what Bitt is saying *might* be applicable to the gadget that is being connected to the empeg, at the other end of that same null modem cable. But the empeg software itself doesn't care about RTS/CTS DTR/DSR CD/RD etc.. for serial port communications. So those are all "don't care" lines from that point of view, and most of them are not connected internally regardless.

However, *some* of those extraneous signals *are* actually connected to stuff inside the empeg, but they are used for things like "carphone mute", "headlight sense", etc..
So having them wired up could be bad regardless.

Cheers