I counsel caution.  MacPPC serial has historically been less than
completely reliable.  It has been "good enough" for console, but
that's about it, and as far as I can tell, not reliable for that.

I'm hoping that the improvements in 2.1/3.0 help.

-dgl-

>Ok folks, I have just built this cable:
>
>http://www.netbsd.org/Documentation/Hardware/Misc/serial.html
>
>		Modem MiniDIN8 to DB25 (Macintosh, non-null modem)
>		Note that RxD+ is shorted to ground, and that TxD+ and GPi
>are floating. You should have the short as close to the DB25 as possible,
>instead of near the MiniDIN8. If possible have the RxD+ and RxD- as a
>twisted pair. 
>		MiniDIN8           DB25
>		--------          ----
>		1 HSKo ----------- 4 RTS
>		2 HSKi ----------- 5 CTS
>		3 TxD- ----------- 2 TxD
>		5 RxD- ----------- 3 RxD
>		4 GND  ---+
>		          +------- 7 GND
>		8 RxD+ ---+
>		6 TxD+ ---x
>		7 GPi  ---x
>
>What on earth is going on?
>
>I've tested it on both printer and modem ports on the mac, Ive had the pc
>set to 38400 8N1, 9600 8N1 - tried it on two different
>Pc's - and nothing!
>
>What am I doing wrong people?
>
>James