Directserial isn't implemented on MAC.

This should be removed from the config file then.

Could I configure serial1=modem
I guess the part that I don't understand is, on windows you alread have com1 and com2 so you just set realport=com1
but on the mac, you don't have such a thing. they are all /dev/tty ports. I tried using realport:/dev/tty.keyserial1 but that didn't work. It was just a shot in the dark and was about the only thing I could come up with.
Any talk of implementing this? Guess my next step would be to program this directly on the mac but that would be quite an undertaking for me since I don't know C or Xcode. Willing to learn it, but that would be quite some time away. Looking for a quick fix for now.
Thanks

The Linux implementation is more or less POSIX compatible. If the MAC uses that interface too it might be not so hard to implement. Should be done by somebody who has a MAC though 😉

There is a newcomer somewhere here at VOGONS with both a Mac, a compiler and knowledge on how to use both. He(?) did some work on getting low-level CD-ROM access to work, but I am not sure if the patch got approved or not. Anyway.... he might be your ticket get the serial ports to work, but remember that DOSBox' primary goals are game-compatiblity, and not about supporting seldom used hardware.