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7.4
U105 (Micro-controller: W78E65P-40)
Pin
Symbol
I/O
Description
1 P4.2/INT3
A bi-directional I/O port with alternate function.
2 P1,0/T2
O
Enable panel power on
3 P1.1/T2EX
O
Enable CCFL work
4
P1.2
I
VGA cable detection
5 P1.3/PWM0
O
provide alternated function of PWM Volume
6 P1.4/PWM1
O
provide alternated function of PWM Green LED
7 P1.5/PWM2
O
provide alternated function of PWM Orange LED
8 P1.6/PWM3
Function is the same as that of standard 8052
9 P1.7/PWM4
Function is the same as that of standard 8052
10
RST
I
Reset control pin
11 P3.0/RXD
SCL line of I2C for EDID, debug function
12 P4.3/INT2
PORT 4: A bi-directional I/O port with alternate
13 P3.1/TXD
SDA line of I2C for EDID, debug function
14 P3.2/INT0
I
Interrupt request control pin
15 P3.3/INT1
O
Shut Down Volume Mute
16 P3.4/T0
O
SCL line of I2C communication with EEPROM
17 P3.5/T1
I/O
SDA line of I2C communication with EEPROM
18 P3.6/WR
I
DVI cable detection
19 P3.7/RD
O
EEPROM write protection control for DVI EDID
20
XTAL2
Crystal 22.1184MHz In
21
XTAL1
Crystal 22.1184MHz out
22
GND
Sink voltage ground
23 P4.0
A bi-directional I/O port with alternate function.
24 P2.0/A8
DC power on/off control
25 P2.1/A9
OSD “
►
” control to adjust value to increase
26 P2.2/A10
OSD “
◄
” control to adjust value to decrease
27 P2.3/A11
Selection of menu command listed
28 P2.4/A12
OSD page selection
29 P2.5/A13
Auto adjustment control
30 P2.6/A14
A bi-directional I/O port with internal pull-ups
31 P2.7/A15
A bi-directional I/O port with internal pull-ups
32
PSEN
Program Store Enable
33 ALE
Address
Latch
Enable
34 P4.1
A bi-directional I/O port with alternate function
35 EA
I
External Access Enable
36
P0.7/AD7
I/O
DDR Direct Bus Communication with Scaler
37
P0.6/AD6
I/O
DDR Direct Bus Communication with Scaler
38
P0.5/AD5
I/O
DDR Direct Bus Communication with Scaler
39
P0.4/AD4
I/O
DDR Direct Bus Communication with Scaler
40
P0.3/AD3
I/O
WRZ line of DDR Direct Bus
41
P0.2/AD2
I/O
RDZ line of DDR Direct Bus
42
P0.1/AD1
I/O
ALE line of DDR Direct Bus
43 P0.0/AD0
O
Hardware reset to Scaler
44
+5V
I
+5V for MCU working voltage
14
ViewSonic Corporation
Co
nfidential
-
Do
Not
Copy
VA902/b
Содержание VA902B - 19" LCD Monitor
Страница 32: ...6 Black Screen and backlight turn on 29 ViewSonic Corporation Confidential Do Not Copy VA902 b...
Страница 49: ...46 ViewSonic Corporation Confidential Do Not Copy VA902 b 9 PCB Layout Main board Top layout...
Страница 50: ...47 ViewSonic Corporation Confidential Do Not Copy VA902 b POWER board...