Here's what I use on an 850 and an 850SX, with NC-lite from Cadem
Ncnet Lite DNC Set-up
PC Settings
Baud Rate 2400
Parity Even
Data Bits 7
Stop Bits 1
Handshake Hardware
Lathe Settings
Dataline 2400
Data Bits 8
Stop Bits 1
Parity None
Protocol Level 1
LDR Count 0
Add RT No
Form Feed No
You need to have one null at the beginning of the program and one null at the end of the program, or the control will not recognize it. Your DNC program should be able to insert them for you.
There is also a program Cincinnati used for drip feeding and transfer called DCDNC. That is available to download here -
http://tech.groups.yahoo.com/group/ACUGroup/