Octagon PC-500, Руководство пользователя

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CRTs and flat panels PC-500 user’s manual
The factory default configuration for the bias voltage ranges from
+21 to +29 VDC. Other bias voltage ranges and negative polarity are
factory configurable. To verify bias voltage, connect a DC voltage meter
input lead to J5 pin 3 and a reference lead to J5 pin 6. Pin 3 verifies the
voltage level and pin 6 is used as a ground reference.
1. Power on the PC-500.
2. Run LCDBIAS.EXE.
3. A message similar to the following should appear on your display:
PhoenixBIOS(TM) A486 Version 1.03
Copyright (C) 1985-1994 Phoenix Technologies,Ltd.
All Rights Reserved
4. Press <CTRL><+> to raise the voltage or <CTRL><-> to lower the
voltage. Raise or lower the voltage until you obtain a good contrast
display with no washout.
To confirm the LCD bias voltage, place a voltmeter on ground at J5,
pin 6 and also on positive at J5, pin 3.
5. The VEESAFE voltage may require additional adjustments in order to
obtain the proper contrast. Use LCDBIASDW or LCDBIASUP to obtain
the proper contrast.
WARNING!
Since improper voltage levels can severely damage the flat
panel, make sure the PC-500 is configured for the correct
bias voltage before it is connected to the panel.
LCD bias control examples
To change the flat panel bias voltage inside your application, use the
INT 17h functions below.
1. LCDBIAS UP. Write the following program to move the voltage up one
step:
mov ah,0eeh ; LCDBIAS control
mov a1,00h ; up
mov dx,0ffffh
int 17h
2. LCDBIAS DOWN. Write the following program to move the voltage
down one step:
mov ah,0eeh ; LCDBIAS control
mov a1,01h ; down
mov dx,0ffffh
int 17h