Mindray PM-7000, Service Manual

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Chapter 2 Principles
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2.2.6.3 Principle
This module receives the to-be-printed data from the main board, converts them to the dot
matrix data, sends them to the heat-sensitive printer, and drives the printer.
Step Motor Drive Circuit
There is a step motor on the heat-sensitive printer. The step motor drives the paper. This
circuit is used to drive the step motor.
Printer Status Detect Circuit
This circuit detects the status of the heat-sensitive printer, and sends the status information to
the CPU system. The status information includes the position of the paper roller, status of the
heat-sensitive recorder paper and the temperature of the heat-sensitive head.
CPU System
„ Processing the data to be printed;
„ Controlling the heat-sensitive printer and step motor;
„ Collecting data about the status of the heat-sensitive printer, and controlling the
printer;
„
Implementing the communication with the main board.
2.2.7 Button Panel
2.2.7.1 General
This module provides a man-machine interactive interface.
2.2.7.2 Principle diagram
Figure 2-10 Working principle of the button panel
2.2.7.3 Principle
This module detects the input signals of the button panel and control knob, converts the
detected input signals to codes and then sends to the main board. The main board sends
commands to the button panel, which, according to the commands, controls the status of the
LED and the audio process circuit to give auditory/visual alarms.