QMS 1660 Reference Manual page 74

Choices ETX/ACK, None, Robust XON/XOFF, XON/XOFF
Default XON/XOFF
Sets the number of seconds the interface waits for data from the host
before terminating a spooled print job.
Menu Administration/Communications/Serial/Spool Timeout
Choices 00000-99999
Default 00030
Sets the number of stop bits transmitted per character.
Menu Administration/Communications/Serial/Stop Bits
Choices 1 Bit, 2 Bits
Default 1 Bit
Sets the software communication protocol used by the host computer
to control communication with the printer.
Menu Administration/Communications/Serial/Xmit Sw Flow Ctl
Choices ETX/ACK, None, XON/XOFF
Default None
Use the Administration/Communications/Network x / Interface menu to
set the printer-host communication values for an optional network
interface, such as CrownNet. The documentation that comes with the
interface contains complete configuration information.