iSys V12 Thermal Printer - Manual (Page 25)

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THEORY OF OPERATION
5.1 INTRODUCTION
The V12 plotter uses thermal technology to convert data from the host computer into plotted
output. Host data enters the plotter’s main logic circuitry via the data port, and passes through
the interface circuitry. Parallel data enters the data buffer on the main logic board. Control and
status signals enter the main logic board at the same time as the parallel data. The
microcontroller converts the data from parallel to serial, and proceeds to send the serial data to
the printhead. One horizontal line (scan), consisting of a single row of dots, is plotted. The
stepper motor advances the paper for the next scan. The cycle repeats until the plotted or
printed image is finished.
Figure 5-1 illustrates the main plotter functions.
5.2 PLOTTER FUNCTIONS AND FEATURES
Power supply
The thermal printhead, stepper motor, and cooling fans are powered by a 24 Volt, 17 Amp DC
power supply. The power supply features an auto-switchable input, which adapts to different
voltage or frequency inputs, for example 110 Volts AC at 60 Hertz or 220 Volts AC at 50 Hz.
The logic circuitry of the plotter including the thermal printhead is powered by an auto-
switchable 5 volt DC output supply.
Table 5-1 shows the plotter status signals.