RCH
INSTALLATION AND MAINTENANCE MANUAL model TOUCH ME
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9.3 PRINTER CONTROL CIRCUIT
The thermal head is composed of a row of heating elements piloted by a series of
command drivers.
The line of dots to be printed is transmitted by the microprocessor (X1) on the SO-4 line,
synchronized with the CLK-4 signal, and then memorized in the latch register of the printer
head by the /LATCH signal.
The information memorized in the LATCH REGISTER is printed afterwards by piloting the
drivers with the BURN print signal which reports to the STROFE pins of the printer head.
The temperature of the printer head is controlled by the microprocessor by reading the
value of the thermistor (TERM) positioned in the sub layer of the printer component.
The presence of paper in the printer station is controlled by reading the output
of the
optical sensor integrated in the printer’s paper path: the PA-R signal senses the absence
of paper. All the control and command lines report to the microprocessor (X1).
