XPM 200HR™
Thermal Printer Family
HENGSTLER
®
Part No. D 690 074
Mod. No. 4 300113 LEV
page 22 of 32
6.4.2. Interfacing
USB
The USB versions of the XPM 200HR™ printer employ a standard USB interface
cable (5 pin Mini-B connector on the printer end) to communicate from the host to the
printer. Be sure that the Mini-B connector is fully engaged with the mating connector
on the printer. The other end of the cable plugs into the USB port on the host. The
cable length must be limited to under 3 meters.
Once the printer is connected with the host and the driver is installed, be sure to set
the Port in the driver to the appropriate USB port to match the physical host-side
interface cable port.
USB Pinout
Pin
Number
Signal name I/O Function
1
NC
no connection
2
D- I/O
Data -
3
D+ I/O
Data +
4
NC
no connection
5
SGND
I/O Signal Ground
6.5. Paper Supply
6.5.1. Paper Roll Holder
Based on our extensive experience in designing printers, we would urge you to
consider the following topics and implement your paper roll holder design with care.
Large Diameter Rolls:
When using paper rolls over 100 mm in diameter, a spring
buffer, or “dancer bar”, should be considered. This usually takes the form of a spring-
loaded arm under which the paper is placed before feeding it into the printer. As the
printer starts to print, slack is taken up from the paper roll. This starts to lift the arm
against the spring, which puts force on the paper roll and starts it moving slowly. As
more printing takes place the roll gradually accelerates until it’s up to printing speed.
Without the dancer bar, slack paper would be taken up until it was suddenly no longer
slack. Now the printer must accelerate a large, heavy paper roll from zero speed to
full print speed in essentially no time. This can cause the paper advance motor to
stall or the paper to slip against the platen, causing shortened characters until the
paper roll is up to speed.
Spindle Friction:
Another important consideration is spindle friction. As a paper roll
rotates, it slides against the spindle that holds it, assuming a fixed spindle. This
friction will tend to impede the paper roll’s free motion, and is dependent upon the
weight of the roll, the smoothness and material of the spindle, and the smoothness
and material of the paper core. When possible, especially with paper rolls over 100
mm in diameter, design the spindle so that it can rotate, greatly decreasing friction
and drag.
Catch Points:
More paper jams and transport problems are caused by catch points
than any other issue. Make sure that the paper path is free of anything that can
interfere with free paper flow, especially any sharp edges or “pinch points” into which
the paper may stray and become caught.
Alignment:
Any paper roll holder design must hold the paper square to the printer in
all planes. If the paper is angled in any way, it will enter the printer at an angle and
will be more likely to cause paper jams.
