RS-232 Communication Mode Selections
Switch settings described in this section apply only when the printer is connected to
the system with the RS-232 cable. The switch is accessible without removing the
printer covers. (See Figure 4on page 12 to see how to access the switch.)
Baud Rate Selection
SureMark printers support two RS-232 baud rates, 9600 and 19 200. The baud rate
is selected using switch 1 on the RS-232 settings switch. Set the switch as follows:
Switch 1 OFF 9600 baud
Switch 1 ON 19 200 baud
The printer normally ships with switch 1 in the OFF position, which selects the 9600
baud rate.
RS-232 Communications Protocol Selection
SureMark printers support RS-232 protocol using either DTR/DSR or XON/XOFF to
control data transmission. XON/XOFF mode uses system and printer software to
control the flow of data.
Use switch 2 on the RS-232 settings switch to select the mode. Switch settings are:
Switch 2 OFF DTR/DSR control
Switch 2 ON XON/XOFF control (must use with a 3-wire interface)
The printer normally ships with switch 2 in the OFF position, which selects
DTR/DSR control.

DTR/DSR Control

DSR Definition: DSR is an output from the printer. It indicates when the printer is
ready to receive data.
DTR Definition: DTR is an input to the printer. It indicates to the printer that the
system is ready to receive data.
DSR Operation: A DSR signal becomes inactive when the printer is not ready to
receive data (for example, at power-on reset or when its buffer is full).
updated March 18, 2002
Chapter2. Installation Instructions 23