Key Board Description - EDAN SE-1200 Series Service Manual

SE-1200 Series Electrocardiograph Service Manual Overview

3.2.4 Key Board Description

The key board is shown in the figure below. When a key is pressed down, the interrupt logic of
key matrix emits an interrupt signal. After CPU (ATmega161) detects the interrupt signal, it reads
the key by row scan and column scan, and sends values to the main board through the serial port.
Figure 3-5 Key Board Diagram
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