Display Pc Board; Digital Signals; Digital Input Signals - Bayer HealthCare RapidPoint 400 Series Service Manual

Display PC Board

The Display PC board provides the electronics necessary to operate the
following components:
• thermal printer
• touch screen
• liquid crystal display (LCD)
• speaker
In addition, the display board provides the following electrical functions:
• circuitry to provide diagnostic capability
• conversion of ASCII data from the host to actual printed reports
• detection, location, measurement, and reporting of touches on the
touch screen
• generation of the voltage necessary to turn the LCD backlight on
and off

Digital Signals

Digital Input Signals

Input Signal
LCD_ENAB
LCD_DIM
LCD_DU0..7
LCD_DL0..7
LCD_YD
LCD_LP
LCD_XCK
ENAVEE
Rev. C
Description
Enables operation of the LCD.
Turns inverter (providing power to the LCD backlight) on and
off.
Upper byte of LCD data signals.
Lower byte of LCD data signals.
Control signal for the LCD. This signal indicates the start of
a scan (analogous to a vertical sync signal).
Control signal for the LCD. This signal indicates the start of
a new line (analogous to a horizontal sync signal).
Clock signal for the LCD.
Control signal. This signal enables the negative supply for
the LCD.
Electronic System Overview 77
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